Though the earliest written mention of a spherical Earth comes from ancient Greek sources, there is no account of how the sphericity of the Earth was discovered.[10] A plausible explanation is that it was "the experience of travellers that suggested such an explanation for the variation in the observable altitude and the change in the area of circumpolar stars, a change that was quite drastic between Greek settlements"[attribution needed] around the eastern Mediterranean Sea, particularly those between the Nile Delta and Crimea.[11]

In The Histories, written 431–425 BC, Herodotus cast doubt on a report of the Sun observed shining from the north. He stated that the phenomenon was observed during a circumnavigation of Africa undertaken by Phoenician explorers employed by EgyptianpharaohNecho II c. 610–595 BC (The Histories, 4.42) who claimed to have had the Sun on their right when circumnavigating in a clockwise direction. To modern historians, these details confirm the truth of the Phoenicians' report and even open the possibility that the Phoenicians knew about the spherical model. However, nothing certain about their knowledge of geography and navigation has survived.[12]

The Hebrew Bible imagined a three-part world, with the heavens (shamayim) above, earth (eres) in the middle, and the underworld (sheol) below.[13] After the 4th century BCE this was gradually replaced by a Greek scientific cosmology of a spherical earth surrounded by multiple concentric heavens.[14]

Pythagoras

Early Greek philosophers alluded to a spherical Earth, though with some ambiguity.[15]Pythagoras (6th century BC) was among those said to have originated the idea, but this might reflect the ancient Greek practice of ascribing every discovery to one or another of their ancient wise men.[10] Some idea of the sphericity of the Earth seems to have been known to both Parmenides and Empedocles in the 5th century BC,[16] and although the idea cannot reliably be ascribed to Pythagoras,[17] it might nevertheless have been formulated in the Pythagorean school in the 5th century BC[10][16] although some disagree.[18] After the 5th century BC, no Greek writer of repute thought the world was anything but round.[15]

Plato

Plato (427–347 BC) travelled to southern Italy to study Pythagorean mathematics. When he returned to Athens and established his school, Plato also taught his students that Earth was a sphere, though he offered no justifications. "My conviction is that the Earth is a round body in the centre of the heavens, and therefore has no need of air or of any similar force to be a support".[19] If man could soar high above the clouds, Earth would resemble "one of those balls which have leather coverings in twelve pieces, and is decked with various colours, of which the colours used by painters on Earth are in a manner samples."[20] In Timaeus, his one work that was available throughout the Middle Ages in Latin, we read that the Creator "made the world in the form of a globe, round as from a lathe, having its extremes in every direction equidistant from the centre, the most perfect and the most like itself of all figures",[21] though the word "world" here refers to the heavens.

Aristotle (384–322 BC) was Plato's prize student and "the mind of the school".[22] Aristotle observed "there are stars seen in Egypt and [...] Cyprus which are not seen in the northerly regions." Since this could only happen on a curved surface, he too believed Earth was a sphere "of no great size, for otherwise the effect of so slight a change of place would not be quickly apparent." (De caelo, 298a2–10)

Aristotle provided physical and observational arguments supporting the idea of a spherical Earth:

Every portion of the Earth tends toward the centre until by compression and convergence they form a sphere. (De caelo, 297a9–21)

Travelers going south see southern constellations rise higher above the horizon; and

The shadow of Earth on the Moon during a lunar eclipse is round. (De caelo, 297b31–298a10).

The concepts of symmetry, equilibrium and cyclic repetition permeated Aristotle's work. In his Meteorology he divided the world into five climatic zones: two temperate areas separated by a torrid zone near the equator, and two cold inhospitable regions, "one near our upper or northern pole and the other near the ... southern pole," both impenetrable and girdled with ice (Meteorologica, 362a31–35). Although no humans could survive in the frigid zones, inhabitants in the southern temperate regions could exist.

In proposition 2 of the First Book of his treatise "On floating bodies," Archimedes demonstrates that "The surface of any fluid at rest is the surface of a sphere whose centre is the same as that of the earth,"[23]. Subsequently in propositions 8 and 9 of the same work, he assumes the result of proposition 2 that the Earth is a sphere and that the surface of a fluid on it is a sphere centered on the center of the Earth.[24]

Eratosthenes

Eratosthenes, a Greek astronomer from HellenisticLibya (276–194 BC), estimated Earth's circumference around 240 BC. He had heard that in Syene the Sun was directly overhead at the summer solstice whereas in Alexandria it still cast a shadow. Using the differing angles the shadows made as the basis of his trigonometric calculations he estimated a circumference of around 250,000 stades. The length of a 'stade' is not precisely known, but Eratosthenes's figure only has an error of around five to fifteen percent.[25][26][27] Eratosthenes used rough estimates and round numbers, but depending on the length of the stadion, his result is within a margin of between 2% and 20% of the actual meridionalcircumference, 40,008 kilometres (24,860 mi). Note that Eratosthenes could only measure the circumference of the Earth by assuming that the distance to the Sun is so great that the rays of sunlight are practically parallel.[28]

Seventeen hundred years after Eratosthenes, Christopher Columbus studied Eratosthenes's findings before sailing west for the Indies. However, ultimately he rejected Eratosthenes in favour of other maps and arguments that interpreted Earth's circumference to be a third smaller than reality. If, instead, Columbus had accepted Eratosthenes findings, then he may have never gone west, since he didn't have the supplies or funding needed for the much longer voyage.[29]

Posidonius (c. 135 – 51 BC) put faith in Eratosthenes's method, though by observing the star Canopus, rather than the sun in establishing the Earth's circumference. In Ptolemy's Geographia, his result was favoured over that of Eratosthenes. Posidonius furthermore expressed the distance of the sun in earth radii.

From its Greek origins, the idea of a spherical earth, along with much of Greek astronomical thought, slowly spread across the globe and ultimately became the adopted view in all major astronomical traditions.[3][4][5][6]

In the West, the idea came to the Romans through the lengthy process of cross-fertilization with Hellenistic civilization. Many Roman authors such as Cicero and Pliny refer in their works to the rotundity of the earth as a matter of course.[30]

Strabo

When a ship is at the horizon, its lower part is obscured by the Earth's curvature. This was one of the first arguments favouring a round-Earth model.

It has been suggested that seafarers probably provided the first observational evidence that the Earth was not flat, based on observations of the horizon. This argument was put forward by the geographer Strabo (c. 64 BC – 24 AD), who suggested that the spherical shape of the Earth was probably known to seafarers around the Mediterranean Sea since at least the time of Homer,[31] citing a line from the Odyssey[32] as indicating that the poet Homer knew of this as early as the 7th or 8th century BC. Strabo cited various phenomena observed at sea as suggesting that the Earth was spherical. He observed that elevated lights or areas of land were visible to sailors at greater distances than those less elevated, and stated that the curvature of the sea was obviously responsible for this.[33]

Claudius Ptolemy

Claudius Ptolemy (90–168 AD) lived in Alexandria, the centre of scholarship in the 2nd century. In the Almagest, which remained the standard work of astronomy for 1,400 years, he advanced many arguments for the spherical nature of the Earth. Among them was the observation that when a ship is sailing towards mountains, observers note these seem to rise from the sea, indicating that they were hidden by the curved surface of the sea. He also gives separate arguments that the Earth is curved north-south and that it is curved east-west.[34]

He compiled an eight-volume Geographia covering what was known about the earth. The first part of the Geographia is a discussion of the data and of the methods he used. As with the model of the solar system in the Almagest, Ptolemy put all this information into a grand scheme. He assigned coordinates to all the places and geographic features he knew, in a grid that spanned the globe (although most of this has been lost). Latitude was measured from the equator, as it is today, but Ptolemy preferred to express it as the length of the longest day rather than degrees of arc (the length of the midsummer day increases from 12h to 24h as you go from the equator to the polar circle). He put the meridian of 0 longitude at the most western land he knew, the Canary Islands.

Ptolemy also devised and provided instructions on how to create maps both of the whole inhabited world (oikoumenè) and of the Roman provinces. In the second part of the Geographia, he provided the necessary topographic lists, and captions for the maps. His oikoumenè spanned 180 degrees of longitude from the Canary Islands in the Atlantic Ocean to China, and about 81 degrees of latitude from the Arctic to the East Indies and deep into Africa. Ptolemy was well aware that he knew about only a quarter of the globe.

Late Antiquity

Knowledge of the spherical shape of the Earth was received in scholarship of Late Antiquity as a matter of course, in both Neoplatonism and Early Christianity. Calcidius's fourth-century Latin commentary on and translation of Plato's Timaeus, which was one of the few examples of Greek scientific thought that was known in the Early Middle Ages, discussed Hipparchus's use of the geometrical circumstances of eclipses to compute the relative diameters of the Sun, Earth, and Moon.[35][36]

Theological doubt informed by the flat Earth model implied in the Hebrew Bible inspired some early Christian scholars such as Lactantius, John Chrysostom and Athanasius of Alexandria, but this remained an eccentric current. Learned Christian authors such as Basil of Caesarea, Ambrose and Augustine of Hippo were clearly aware of the sphericity of the Earth. "Flat Earthism" lingered longest in Syriac Christianity, which tradition laid greater importance on a literalist interpretation of the Old Testament. Authors from that tradition, such as Cosmas Indicopleustes, presented the Earth as flat as late as in the 6th century. This last remnant of the ancient model of the cosmos disappeared during the 7th century. From the 8th century and the beginning medieval period, "no cosmographer worthy of note has called into question the sphericity of the Earth."[37]

Greek ethnographer Megasthenes, c. 300 BC, has been interpreted as stating that the contemporary Brahmans believed in a spherical earth as the center of the universe.[38] With the spread of Greek culture in the east, Hellenistic astronomy filtered eastwards to ancient India where its profound influence became apparent in the early centuries AD.[39] The Greek concept of an Earth surrounded by the spheres of the planets and that of the fixed stars, vehemently supported by astronomers like Varahamihir and Brahmagupta, strengthened the astronomical principles. Some ideas were found possible to preserve, although in altered form.[39][40]

The works of the classical Indian astronomer and mathematician, Aryabhatta (476–550 AD), deal with the sphericity of the Earth and the motion of the planets. The final two parts of his Sanskrit magnum opus, the Aryabhatiya, which were named the Kalakriya ("reckoning of time") and the Gol ("sphere"), state that the Earth is spherical and that its circumference is 4,967 yojanas. In modern units this is 39,968 km (24,835 mi), close to the current equatorial value of 40,075 km (24,901 mi).[41][42]

Spherical earth with the four seasons. Illustration in 12th century book Liber Divinorum Operum by Hildegard of Bingen

Isidore of Seville

Bishop Isidore of Seville (560–636) taught in his widely read encyclopedia, The Etymologies, that the Earth was "round".[44] The bishop's confusing exposition and choice of imprecise Latin terms have divided scholarly opinion on whether he meant a sphere or a disk or even whether he meant anything specific.[45] Notable recent scholars claim that he taught a spherical earth.[46] Isidore did not admit the possibility of people dwelling at the antipodes, considering them as legendary[47] and noting that there was no evidence for their existence.[48]

Bede the Venerable

The monk Bede (c. 672–735) wrote in his influential treatise on computus, The Reckoning of Time, that the Earth was round. He explained the unequal length of daylight from "the roundness of the Earth, for not without reason is it called 'the orb of the world' on the pages of Holy Scripture and of ordinary literature. It is, in fact, set like a sphere in the middle of the whole universe." (De temporum ratione, 32). The large number of surviving manuscripts of The Reckoning of Time, copied to meet the Carolingian requirement that all priests should study the computus, indicates that many, if not most, priests were exposed to the idea of the sphericity of the Earth.[49]Ælfric of Eynsham paraphrased Bede into Old English, saying, "Now the Earth's roundness and the Sun's orbit constitute the obstacle to the day's being equally long in every land."[50]

Bede was lucid about earth's sphericity, writing "We call the earth a globe, not as if the shape of a sphere were expressed in the diversity of plains and mountains, but because, if all things are included in the outline, the earth's circumference will represent the figure of a perfect globe... For truly it is an orb placed in the centre of the universe; in its width it is like a circle, and not circular like a shield but rather like a ball, and it extends from its centre with perfect roundness on all sides."[51]

Anania Shirakatsi

The 7th-century Armenian scholar Anania Shirakatsi described the world as "being like an egg with a spherical yolk (the globe) surrounded by a layer of white (the atmosphere) and covered with a hard shell (the sky)."[52]

Another estimate given by his astronomers was 56​2⁄3 Arabic miles (111.8 km) per degree, which corresponds to a circumference of 40,248 km, very close to the currently modern values of 111.3 km per degree and 40,068 km circumference, respectively.[57]

Al-Farghānī (Latinized as Alfraganus) was a Persian astronomer of the 9th century involved in measuring the diameter of the Earth, and commissioned by Al-Ma'mun. His estimate given above for a degree (56​2⁄3 Arabic miles) was much more accurate than the 60​2⁄3 Roman miles (89.7 km) given by Ptolemy. Christopher Columbus uncritically used Alfraganus's figure as if it were in Roman miles instead of in Arabic miles, in order to prove a smaller size of the Earth than that propounded by Ptolemy.[59]

Biruni

Biruni's Method for calculation of Earth's radius

Abu Rayhan Biruni (973–1048) used a new method to accurately compute the Earth's circumference, by which he arrived at a value that was close to modern values for the Earth's circumference.[60] His estimate of 6,339.6 km for the Earth radius was only 31.4 km less than the modern mean value of 6,371.0 km.[61] In contrast to his predecessors, who measured the Earth's circumference by sighting the Sun simultaneously from two different locations, Biruni developed a new method of using trigonometric calculations based on the angle between a plain and mountain top. This yielded more accurate measurements of the Earth's circumference and made it possible for a single person to measure it from a single location.[62][63] Biruni's method was intended to avoid "walking across hot, dusty deserts," and the idea came to him when he was on top of a tall mountain in India. From the top of the mountain, he sighted the angle to the horizon which, along with the mountain's height (which he calculated beforehand), allowed him to calculate the curvature of the Earth.[64][65] He also made use of algebra to formulate trigonometric equations and used the astrolabe to measure angles.[66]

"Important contributions to geodesy and geography were also made by Biruni. He introduced techniques to measure the earth and distances on it using triangulation. He found the radius of the earth to be 6339.6 km, a value not obtained in the West until the 16th century. His Masudic canon contains a table giving the coordinates of six hundred places, almost all of which he had direct knowledge."[67]

Applications

Muslim scholars who held to the round Earth theory used it for a quintessentially Islamic purpose: to calculate the distance and direction from any given point on the Earth to Mecca.[68] This determined the Qibla, or Muslim direction of prayer.

A terrestrial globe (Kura-i-ard) was among the presents sent by the Persian Muslim astronomer Jamal-al-Din to Kubla Khan's Chinese court in 1267. It was made of wood on which "seven parts of water are represented in green, three parts of land in white, with rivers, lakes etc."[69] Ho Peng Yoke remarks that "it did not seem to have any general appeal to the Chinese in those days".[70]

Saint Hildegard (Hildegard von Bingen, 1098–1179), depicted the spherical earth several times in her work Liber Divinorum Operum.[71]

Johannes de Sacrobosco (c. 1195 – c. 1256 AD) wrote a famous work on Astronomy called Tractatus de Sphaera, based on Ptolemy, which primarily considers the sphere of the sky. However, it contains clear proofs of the earth's sphericity in the first chapter.[72][73]

Many scholastic commentators on Aristotle's On the Heavens and Sacrobosco's Treatise on the Sphere unanimously agreed that the earth is spherical or round.[74] Grant observes that no author who had studied at a medieval university thought that the earth was flat.[75]

Dante's Divine Comedy, written in Italian in the early 14th century, portrays Earth as a sphere, discussing implications such as the different stars visible in the southern hemisphere, the altered position of the sun, and the various timezones of the Earth.

The first direct demonstration of Earth's sphericity came in the form of the first circumnavigation in history, an expedition captained by Portuguese explorer Ferdinand Magellan.[76] The expedition was financed by the Spanish Crown. On August 10, 1519, the five ships under Magellan's command departed from Seville. They crossed the Atlantic Ocean, passed through what is now called the Strait of Magellan, crossed the Pacific, and arrived in Cebu, where Magellan was killed by Philippine natives in a battle. His second in command, the Spaniard Juan Sebastián Elcano, continued the expedition and, on September 6, 1522, arrived at Seville, completing the circumnavigation. Charles I of Spain, in recognition of his feat, gave Elcano a coat of arms with the motto Primus circumdedisti me (in Latin, "You went around me first").[77]

A circumnavigation alone does not prove that the earth is spherical. It could be cylindric or irregularly globular or one of many other shapes. Still, combined with trigonometric evidence of the form used by Eratosthenes 1,700 years prior, the Magellan expedition removed any reasonable doubt in educated circles in Europe.[78] The Transglobe Expedition (1979-1982) was the first expedition to make a circumpolar circumnavigation, traveling the world "vertically" traversing both of the poles of rotation using only surface transport.

In the 17th century, the idea of a spherical Earth, now considerably advanced by Western astronomy, ultimately spread to Ming China, when Jesuit missionaries, who held high positions as astronomers at the imperial court, successfully challenged the Chinese belief that the Earth was flat and square.[79][80][81]

The Ge zhi cao (格致草) treatise of Xiong Mingyu (熊明遇) published in 1648 showed a printed picture of the Earth as a spherical globe, with the text stating that "the round Earth certainly has no square corners".[82] The text also pointed out that sailing ships could return to their port of origin after circumnavigating the waters of the Earth.[82]

The influence of the map is distinctly Western, as traditional maps of Chinese cartography held the graduation of the sphere at 365.25 degrees, while the Western graduation was of 360 degrees. Also of interest to note is on one side of the world, there is seen towering Chinese pagodas, while on the opposite side (upside-down) there were European cathedrals.[82] The adoption of European astronomy, facilitated by the failure of indigenous astronomy to make progress, was accompanied by a sinocentric reinterpretation that declared the imported ideas Chinese in origin:

European astronomy was so much judged worth consideration that numerous Chinese authors developed the idea that the Chinese of antiquity had anticipated most of the novelties presented by the missionaries as European discoveries, for example, the rotundity of the Earth and the "heavenly spherical star carrier model." Making skillful use of philology, these authors cleverly reinterpreted the greatest technical and literary works of Chinese antiquity. From this sprang a new science wholly dedicated to the demonstration of the Chinese origin of astronomy and more generally of all European science and technology.[79]

Although mainstream Chinese science until the 17th century held the view that the earth was flat, square, and enveloped by the celestial sphere, this idea was criticized by the Jin-dynasty scholar Yu Xi (fl. 307-345), who suggested that the Earth could be either square or round, in accordance with the shape of the heavens.[83] The Yuan-dynasty mathematician Li Ye (c. 1192-1279) firmly argued that the Earth was spherical, just like the shape of the heavens only smaller, since a square Earth would hinder the movement of the heavens and celestial bodies in his estimation.[84] The 17th-century Ge zhi cao treatise also used the same terminology to describe the shape of the Earth that the Eastern-Han scholar Zhang Heng (78-139 AD) had used to describe the shape of the sun and moon (i.e. that the former was as round as a crossbow bullet, and the latter was the shape of a ball).[85]

Geodesy, also called geodetics, is the scientific discipline that deals with the measurement and representation of the Earth, its gravitational field and geodynamic phenomena (polar motion, Earth tides, and crustal motion) in three-dimensional time-varying space.

Geodesy is primarily concerned with positioning and the gravity field and geometrical aspects of their temporal variations, although it can also include the study of Earth's magnetic field. Especially in the German speaking world, geodesy is divided into geomensuration ("Erdmessung" or "höhere Geodäsie"), which is concerned with measuring the Earth on a global scale, and surveying ("Ingenieurgeodäsie"), which is concerned with measuring parts of the surface.

as the shape of Earth's land surface as it rises above and falls below the sea.

As the science of geodesy measured Earth more accurately, the shape of the geoid was first found not to be a perfect sphere but to approximate an oblate spheroid, a specific type of ellipsoid. More recent measurements have measured the geoid to unprecedented accuracy, revealing mass concentrations beneath Earth's surface.

^ abAdoption by China via European science: Jean-Claude Martzloff, “Space and Time in Chinese Texts of Astronomy and of Mathematical Astronomy in the Seventeenth and Eighteenth Centuries”, Chinese Science 11 (1993–94): 66–92 (69) and Christopher Cullen, "A Chinese Eratosthenes of the Flat Earth: A Study of a Fragment of Cosmology in Huai Nan tzu 淮 南 子", Bulletin of the School of Oriental and African Studies, Vol. 39, No. 1 (1976), pp. 106–127 (107)

^E. At. Schwanbeck (1877). Ancient India as described by Megasthenês and Arrian; being a translation of the fragments of the Indika of Megasthenês collected by Dr. Schwanbeck, and of the first part of the Indika of Arrian. p. 101.

^Referring to Isidore's five circles in De Natura Rerum X 5, ERnest Brehaut wrote: "The explanation of the passage and of the figure which illustrates it seems to be that Isidore accepted the terminology of the spherical earth from Hyginus without taking the time to understand it—if indeed he had the ability to do so—and applied it without compunction to the flat earth." Ernest Brehaut (1912). Encyclopedist of the Flat Earth. p. 30. Similarly, J. Fontaine refers to this passage as a "scientific absurdity".Isidore of Seville (1960). J. Fontaine, ed. Traité de la Nature. p. 16.

^David A. King, Astronomy in the Service of Islam, (Aldershot (U.K.): Variorum), 1993.

^Gharā'ib al-funūn wa-mulah al-`uyūn (The Book of Curiosities of the Sciences and Marvels for the Eyes), 2.1 "On the mensuration of the Earth and its division into seven climes, as related by Ptolemy and others," (ff. 22b–23a)[2]

1.
Earth radius
–
Earth radius is the distance from the Earths center to its surface, about 6,371 km. This length is used as a unit of distance, especially in astronomy and geology. This article deals primarily with spherical and ellipsoidal models of the Earth, see Figure of the Earth for a more complete discussion of the models. The Earth is only approximately spherical, so no single value serves as its natural radius, distances from points on the surface to the center range from 6,353 km to 6,384 km. Several different ways of modeling the Earth as a sphere each yield a mean radius of 6,371 km. It can also mean some kind of average of such distances, Aristotle, writing in On the Heavens around 350 BC, reports that the mathematicians guess the circumference of the Earth to be 400,000 stadia. Due to uncertainty about which stadion variant Aristotle meant, scholars have interpreted Aristotles figure to be anywhere from highly accurate to almost double the true value, the first known scientific measurement and calculation of the radius of the Earth was performed by Eratosthenes about 240 BC. Estimates of the accuracy of Eratosthenes’s measurement range from within 0. 5% to within 17%, as with Aristotles report, uncertainty in the accuracy of his measurement is due to modern uncertainty over which stadion definition he used. Earths rotation, internal density variations, and external tidal forces cause its shape to deviate systematically from a perfect sphere, local topography increases the variance, resulting in a surface of profound complexity. Our descriptions of the Earths surface must be simpler than reality in order to be tractable, hence, we create models to approximate characteristics of the Earths surface, generally relying on the simplest model that suits the need. Each of the models in use involve some notion of the geometric radius. Strictly speaking, spheres are the solids to have radii. In the case of the geoid and ellipsoids, the distance from any point on the model to the specified center is called a radius of the Earth or the radius of the Earth at that point. It is also common to refer to any mean radius of a model as the radius of the earth. When considering the Earths real surface, on the hand, it is uncommon to refer to a radius. Rather, elevation above or below sea level is useful, regardless of the model, any radius falls between the polar minimum of about 6,357 km and the equatorial maximum of about 6,378 km. Hence, the Earth deviates from a sphere by only a third of a percent. While specific values differ, the concepts in this article generalize to any major planet

2.
Medieval
–
In the history of Europe, the Middle Ages or Medieval Period lasted from the 5th to the 15th century. It began with the fall of the Western Roman Empire and merged into the Renaissance, the Middle Ages is the middle period of the three traditional divisions of Western history, classical antiquity, the medieval period, and the modern period. The medieval period is subdivided into the Early, High. Population decline, counterurbanisation, invasion, and movement of peoples, the large-scale movements of the Migration Period, including various Germanic peoples, formed new kingdoms in what remained of the Western Roman Empire. In the seventh century, North Africa and the Middle East—once part of the Byzantine Empire—came under the rule of the Umayyad Caliphate, although there were substantial changes in society and political structures, the break with classical antiquity was not complete. The still-sizeable Byzantine Empire survived in the east and remained a major power, the empires law code, the Corpus Juris Civilis or Code of Justinian, was rediscovered in Northern Italy in 1070 and became widely admired later in the Middle Ages. In the West, most kingdoms incorporated the few extant Roman institutions, monasteries were founded as campaigns to Christianise pagan Europe continued. The Franks, under the Carolingian dynasty, briefly established the Carolingian Empire during the later 8th, the Crusades, first preached in 1095, were military attempts by Western European Christians to regain control of the Holy Land from Muslims. Kings became the heads of centralised nation states, reducing crime and violence, intellectual life was marked by scholasticism, a philosophy that emphasised joining faith to reason, and by the founding of universities. Controversy, heresy, and the Western Schism within the Catholic Church paralleled the conflict, civil strife. Cultural and technological developments transformed European society, concluding the Late Middle Ages, the Middle Ages is one of the three major periods in the most enduring scheme for analysing European history, classical civilisation, or Antiquity, the Middle Ages, and the Modern Period. Medieval writers divided history into periods such as the Six Ages or the Four Empires, when referring to their own times, they spoke of them as being modern. In the 1330s, the humanist and poet Petrarch referred to pre-Christian times as antiqua, leonardo Bruni was the first historian to use tripartite periodisation in his History of the Florentine People. Bruni and later argued that Italy had recovered since Petrarchs time. The Middle Ages first appears in Latin in 1469 as media tempestas or middle season, in early usage, there were many variants, including medium aevum, or middle age, first recorded in 1604, and media saecula, or middle ages, first recorded in 1625. The alternative term medieval derives from medium aevum, tripartite periodisation became standard after the German 17th-century historian Christoph Cellarius divided history into three periods, Ancient, Medieval, and Modern. The most commonly given starting point for the Middle Ages is 476, for Europe as a whole,1500 is often considered to be the end of the Middle Ages, but there is no universally agreed upon end date. English historians often use the Battle of Bosworth Field in 1485 to mark the end of the period

3.
Earth
–
Earth, otherwise known as the World, or the Globe, is the third planet from the Sun and the only object in the Universe known to harbor life. It is the densest planet in the Solar System and the largest of the four terrestrial planets, according to radiometric dating and other sources of evidence, Earth formed about 4.54 billion years ago. Earths gravity interacts with objects in space, especially the Sun. During one orbit around the Sun, Earth rotates about its axis over 365 times, thus, Earths axis of rotation is tilted, producing seasonal variations on the planets surface. The gravitational interaction between the Earth and Moon causes ocean tides, stabilizes the Earths orientation on its axis, Earths lithosphere is divided into several rigid tectonic plates that migrate across the surface over periods of many millions of years. About 71% of Earths surface is covered with water, mostly by its oceans, the remaining 29% is land consisting of continents and islands that together have many lakes, rivers and other sources of water that contribute to the hydrosphere. The majority of Earths polar regions are covered in ice, including the Antarctic ice sheet, Earths interior remains active with a solid iron inner core, a liquid outer core that generates the Earths magnetic field, and a convecting mantle that drives plate tectonics. Within the first billion years of Earths history, life appeared in the oceans and began to affect the Earths atmosphere and surface, some geological evidence indicates that life may have arisen as much as 4.1 billion years ago. Since then, the combination of Earths distance from the Sun, physical properties, in the history of the Earth, biodiversity has gone through long periods of expansion, occasionally punctuated by mass extinction events. Over 99% of all species that lived on Earth are extinct. Estimates of the number of species on Earth today vary widely, over 7.4 billion humans live on Earth and depend on its biosphere and minerals for their survival. Humans have developed diverse societies and cultures, politically, the world has about 200 sovereign states, the modern English word Earth developed from a wide variety of Middle English forms, which derived from an Old English noun most often spelled eorðe. It has cognates in every Germanic language, and their proto-Germanic root has been reconstructed as *erþō, originally, earth was written in lowercase, and from early Middle English, its definite sense as the globe was expressed as the earth. By early Modern English, many nouns were capitalized, and the became the Earth. More recently, the name is simply given as Earth. House styles now vary, Oxford spelling recognizes the lowercase form as the most common, another convention capitalizes Earth when appearing as a name but writes it in lowercase when preceded by the. It almost always appears in lowercase in colloquial expressions such as what on earth are you doing, the oldest material found in the Solar System is dated to 4. 5672±0.0006 billion years ago. By 4. 54±0.04 Gya the primordial Earth had formed, the formation and evolution of Solar System bodies occurred along with the Sun

4.
Water
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Water is a transparent and nearly colorless chemical substance that is the main constituent of Earths streams, lakes, and oceans, and the fluids of most living organisms. Its chemical formula is H2O, meaning that its molecule contains one oxygen, Water strictly refers to the liquid state of that substance, that prevails at standard ambient temperature and pressure, but it often refers also to its solid state or its gaseous state. It also occurs in nature as snow, glaciers, ice packs and icebergs, clouds, fog, dew, aquifers, Water covers 71% of the Earths surface. It is vital for all forms of life. Only 2. 5% of this water is freshwater, and 98. 8% of that water is in ice and groundwater. Less than 0. 3% of all freshwater is in rivers, lakes, and the atmosphere, a greater quantity of water is found in the earths interior. Water on Earth moves continually through the cycle of evaporation and transpiration, condensation, precipitation. Evaporation and transpiration contribute to the precipitation over land, large amounts of water are also chemically combined or adsorbed in hydrated minerals. Safe drinking water is essential to humans and other even though it provides no calories or organic nutrients. There is a correlation between access to safe water and gross domestic product per capita. However, some observers have estimated that by 2025 more than half of the population will be facing water-based vulnerability. A report, issued in November 2009, suggests that by 2030, in developing regions of the world. Water plays an important role in the world economy, approximately 70% of the freshwater used by humans goes to agriculture. Fishing in salt and fresh water bodies is a source of food for many parts of the world. Much of long-distance trade of commodities and manufactured products is transported by boats through seas, rivers, lakes, large quantities of water, ice, and steam are used for cooling and heating, in industry and homes. Water is an excellent solvent for a variety of chemical substances, as such it is widely used in industrial processes. Water is also central to many sports and other forms of entertainment, such as swimming, pleasure boating, boat racing, surfing, sport fishing, Water is a liquid at the temperatures and pressures that are most adequate for life. Specifically, at atmospheric pressure of 1 bar, water is a liquid between the temperatures of 273.15 K and 373.15 K

5.
Greek philosophy
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Ancient Greek philosophy arose in the 6th century BC and continued throughout the Hellenistic period and the period in which Ancient Greece was part of the Roman Empire. Philosophy was used to sense out of the world in a non-religious way. It dealt with a variety of subjects, including political philosophy, ethics, metaphysics, ontology, logic, biology, rhetoric. Many philosophers around the world agree that Greek philosophy has influenced much of Western culture since its inception, alfred North Whitehead once noted, The safest general characterization of the European philosophical tradition is that it consists of a series of footnotes to Plato. Clear, unbroken lines of lead from ancient Greek and Hellenistic philosophers to Early Islamic philosophy, the European Renaissance. Some claim that Greek philosophy, in turn, was influenced by the wisdom literature. But they taught themselves to reason, Philosophy as we understand it is a Greek creation. Subsequent philosophic tradition was so influenced by Socrates as presented by Plato that it is conventional to refer to philosophy developed prior to Socrates as pre-Socratic philosophy. The periods following this, up to and after the wars of Alexander the Great, are those of classical Greek, the pre-Socratics were primarily concerned with cosmology, ontology and mathematics. They were distinguished from non-philosophers insofar as they rejected mythological explanations in favor of reasoned discourse, Thales of Miletus, regarded by Aristotle as the first philosopher, held that all things arise from water. It is not because he gave a cosmogony that John Burnet calls him the first man of science, according to tradition, Thales was able to predict an eclipse and taught the Egyptians how to measure the height of the pyramids. He began from the observation that the world seems to consist of opposites, therefore, they cannot truly be opposites but rather must both be manifestations of some underlying unity that is neither. This underlying unity could not be any of the classical elements, for example, water is wet, the opposite of dry, while fire is dry, the opposite of wet. Anaximenes in turn held that the arche was air, although John Burnet argues that by this he meant that it was a transparent mist, the aether. Xenophanes was born in Ionia, where the Milesian school was at its most powerful, Burnet says that Xenophanes was not, however, a scientific man, with many of his naturalistic explanations having no further support than that they render the Homeric gods superfluous or foolish. He has been claimed as an influence on Eleatic philosophy, although that is disputed, and a precursor to Epicurus, a representative of a total break between science and religion. Pythagoras lived at roughly the time that Xenophanes did and, in contrast to the latter. Parmenides of Elea cast his philosophy against those who held it is and is not the same, and all travel in opposite directions, —presumably referring to Heraclitus

6.
History of geodesy
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Geodesy, also named geodetics, is the scientific discipline that deals with the measurement and representation of the Earth. The history of geodesy began in antiquity and blossomed during the Age of Enlightenment, early ideas about the figure of the Earth held the Earth to be flat, and the heavens a physical dome spanning over it. The early Greeks, in their speculation and theorizing, ranged from the flat disc advocated by Homer to the spherical body postulated by Pythagoras, pythagorass idea was supported later by Aristotle. Pythagoras was a mathematician and to him the most perfect figure was a sphere and he reasoned that the gods would create a perfect figure and therefore the Earth was created to be spherical in shape. Anaximenes, an early Greek philosopher, believed strongly that the Earth was rectangular in shape, since the spherical shape was the most widely supported during the Greek Era, efforts to determine its size followed. Platos figure was a guess and Archimedes a more conservative approximation, in Egypt, a Greek scholar and philosopher, Eratosthenes, is said to have made more explicit measurements. He had heard that on the longest day of the summer solstice, at the same time, he observed the sun was not directly overhead at Alexandria, instead, it cast a shadow with the vertical equal to 1/50th of a circle. Legend has it that he had someone walk from Alexandria to Syene to measure the distance, the circumference of the Earth is 24,902 mi. Over the poles it is more precisely 40,008 km or 24,860 mi, the actual unit of measure used by Eratosthenes was the stadion. No one knows for sure what his stadion equals in modern units, had the experiment been carried out as described, it would not be remarkable if it agreed with actuality. What is remarkable is that the result was only about 0. 4% too high. A parallel later ancient measurement of the size of the Earth was made by another Greek scholar and he is said to have noted that the star Canopus was hidden from view in most parts of Greece but that it just grazed the horizon at Rhodes. Posidonius is supposed to have measured the elevation of Canopus at Alexandria and he assumed the distance from Alexandria to Rhodes to be 5000 stadia, and so he computed the Earths circumference in stadia as 48 times 5000 =240,000. Some scholars see these results as luckily semi-accurate due to cancellation of errors, the abovementioned larger and smaller sizes of the Earth were those used by Claudius Ptolemy at different times,252,000 stadia in his Almagest and 180,000 stadia in his later Geography. The Indian mathematician Aryabhata was a pioneer of mathematical astronomy and he describes the earth as being spherical and that it rotates on its axis, among other things in his work Āryabhaṭīya. Aryabhatiya is divided into four sections, the discovery that the earth rotates on its own axis from west to east is described in Aryabhatiya. Aryabhata gives the radii of the orbits of the planets in terms of the Earth-Sun distance as essentially their periods of rotation around the Sun and he also gave the correct explanation of lunar and solar eclipses and that the Moon shines by reflecting sunlight. The Muslim scholars, who held to the spherical Earth theory, used it to calculate the distance and this determined the Qibla, or Muslim direction of prayer

7.
Figure of the Earth
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The expression figure of the Earth has various meanings in geodesy according to the way it is used and the precision with which the Earths size and shape is to be defined. The actual topographic surface is most apparent with its variety of land forms and this is, in fact, the surface on which actual Earth measurements are made. The topographic surface is generally the concern of topographers and hydrographers, the Pythagorean concept of a spherical Earth offers a simple surface that is mathematically easy to deal with. Many astronomical and navigational computations use it as a representing the Earth. The idea of a planar or flat surface for Earth, however, is sufficient for surveys of small areas, as the local topography is far more significant than the curvature. Plane-table surveys are made for small areas, and no account is taken of the curvature of the Earth. A survey of a city would likely be computed as though the Earth were a surface the size of the city. For such small areas, exact positions can be determined relative to each other without considering the size, in the mid- to late 20th century, research across the geosciences contributed to drastic improvements in the accuracy of the figure of the Earth. The primary utility of this improved accuracy was to provide geographical and gravitational data for the guidance systems of ballistic missiles. This funding also drove the expansion of geoscientific disciplines, fostering the creation, the models for the figure of the Earth vary in the way they are used, in their complexity, and in the accuracy with which they represent the size and shape of the Earth. The simplest model for the shape of the entire Earth is a sphere, the Earths radius is the distance from Earths center to its surface, about 6,371 kilometers. The concept of a spherical Earth dates back to around the 6th century BC, the first scientific estimation of the radius of the earth was given by Eratosthenes about 240 BC, with estimates of the accuracy of Eratosthenes’s measurement ranging from 2% to 15%. The Earth is only approximately spherical, so no single value serves as its natural radius, distances from points on the surface to the center range from 6,353 km to 6,384 km. Several different ways of modeling the Earth as a sphere each yield a mean radius of 6,371 kilometers, regardless of the model, any radius falls between the polar minimum of about 6,357 km and the equatorial maximum of about 6,378 km. The difference 21 kilometers correspond to the polar radius being approximately 0. 3% shorter than the equator radius, since the Earth is flattened at the poles and bulges at the equator, geodesy represents the shape of the earth with an oblate spheroid. The oblate spheroid, or oblate ellipsoid, is an ellipsoid of revolution obtained by rotating an ellipse about its shorter axis and it is the regular geometric shape that most nearly approximates the shape of the Earth. A spheroid describing the figure of the Earth or other body is called a reference ellipsoid. The reference ellipsoid for Earth is called an Earth ellipsoid, an ellipsoid of revolution is uniquely defined by two numbers, two dimensions, or one dimension and a number representing the difference between the two dimensions

8.
Old World
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The Old World consists of Africa, Europe, and Asia, regarded collectively as the part of the world known to Europeans before contact with the Americas. It is used in the context of, and contrast with and these regions were connected via the Silk Road trade route, and they have a pronounced Iron Age period following the Bronze Age. The concept of the three continents in the Old World, viz. Asia, Africa, and Europe, goes back to classical antiquity and their boundaries as defined by Ptolemy and other geographers of antiquity were drawn along the Nile and Don rivers. This definition remained influential throughout the Middle Ages and the Early Modern period, the Old world has areas of North Africa, Eurasia, parts of Papua New Guinea and Solomon Islands. The mainland of Afro-Eurasia has been referred to as the World Island, the term may have been coined by Sir Halford John Mackinder in The Geographical Pivot of History. The equivalent of the Old World had names in some of its ancient cultures, including Midgard in Germanic cosmology, synoptic table of the principal old world prehistoric cultures Afro-Eurasia

9.
Late Antiquity
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Late antiquity is a periodization used by historians to describe the time of transition from classical antiquity to the Middle Ages in mainland Europe, the Mediterranean world, and the Near East. The development of the periodization has generally been accredited to historian Peter Brown, precise boundaries for the period are a continuing matter of debate, but Brown proposes a period between the 3rd and 8th centuries AD. Generally, it can be thought of as from the end of the Roman Empires Crisis of the Third Century to, in the East, the early Islamic period, following the Muslim conquests in the mid–7th century. In the West the end was earlier, with the start of the Early Medieval period typically placed in the 6th century, beginning with Constantine the Great, Christianity was made legal in the Empire, and a new capital was founded at Constantinople. The resultant cultural fusion of Greco-Roman, Germanic and Christian traditions formed the foundations of the subsequent culture of Europe, the term Spätantike, literally late antiquity, has been used by German-speaking historians since its popularization by Alois Riegl in the early 20th century. Concurrently, some migrating Germanic tribes such as the Ostrogoths and Visigoths saw themselves as perpetuating the Roman tradition, Constantine confirmed the legalization of the religion through the so-called Edict of Milan in 313, jointly issued with his rival in the East, Licinius. Monasticism was not the only new Christian movement to appear in Late Antiquity, notable in this regard is the topic of the Fifty Bibles of Constantine. Within the recently legitimized Christian community of the 4th century, a division could be distinctly seen between the laity and an increasingly celibate male leadership. Celibate and detached, the clergy became an elite equal in prestige to urban notables. The Late Antique period also saw a transformation of the political and social basis of life in. The later Roman Empire was in a sense a network of cities, archaeology now supplements literary sources to document the transformation followed by collapse of cities in the Mediterranean basin. Burials within the urban precincts mark another stage in dissolution of traditional urbanistic discipline, overpowered by the attraction of saintly shrines, in Roman Britain, the typical 4th- and 5th-century layer of black earth within cities seems to be a result of increased gardening in formerly urban spaces. A similar though less marked decline in population occurred later in Constantinople. In Europe there was also a decline in urban populations. As a whole, the period of antiquity was accompanied by an overall population decline in almost all Europe. Long-distance markets disappeared, and there was a reversion to a degree of local production and consumption, rather than webs of commerce. The degree and extent of discontinuity in the cities of the Greek East is a moot subject among historians. In the western Mediterranean, the new cities known to be founded in Europe between the 5th and 8th centuries were the four or five Visigothic victory cities

10.
Middle Ages
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In the history of Europe, the Middle Ages or Medieval Period lasted from the 5th to the 15th century. It began with the fall of the Western Roman Empire and merged into the Renaissance, the Middle Ages is the middle period of the three traditional divisions of Western history, classical antiquity, the medieval period, and the modern period. The medieval period is subdivided into the Early, High. Population decline, counterurbanisation, invasion, and movement of peoples, the large-scale movements of the Migration Period, including various Germanic peoples, formed new kingdoms in what remained of the Western Roman Empire. In the seventh century, North Africa and the Middle East—once part of the Byzantine Empire—came under the rule of the Umayyad Caliphate, although there were substantial changes in society and political structures, the break with classical antiquity was not complete. The still-sizeable Byzantine Empire survived in the east and remained a major power, the empires law code, the Corpus Juris Civilis or Code of Justinian, was rediscovered in Northern Italy in 1070 and became widely admired later in the Middle Ages. In the West, most kingdoms incorporated the few extant Roman institutions, monasteries were founded as campaigns to Christianise pagan Europe continued. The Franks, under the Carolingian dynasty, briefly established the Carolingian Empire during the later 8th, the Crusades, first preached in 1095, were military attempts by Western European Christians to regain control of the Holy Land from Muslims. Kings became the heads of centralised nation states, reducing crime and violence, intellectual life was marked by scholasticism, a philosophy that emphasised joining faith to reason, and by the founding of universities. Controversy, heresy, and the Western Schism within the Catholic Church paralleled the conflict, civil strife. Cultural and technological developments transformed European society, concluding the Late Middle Ages, the Middle Ages is one of the three major periods in the most enduring scheme for analysing European history, classical civilisation, or Antiquity, the Middle Ages, and the Modern Period. Medieval writers divided history into periods such as the Six Ages or the Four Empires, when referring to their own times, they spoke of them as being modern. In the 1330s, the humanist and poet Petrarch referred to pre-Christian times as antiqua, leonardo Bruni was the first historian to use tripartite periodisation in his History of the Florentine People. Bruni and later argued that Italy had recovered since Petrarchs time. The Middle Ages first appears in Latin in 1469 as media tempestas or middle season, in early usage, there were many variants, including medium aevum, or middle age, first recorded in 1604, and media saecula, or middle ages, first recorded in 1625. The alternative term medieval derives from medium aevum, tripartite periodisation became standard after the German 17th-century historian Christoph Cellarius divided history into three periods, Ancient, Medieval, and Modern. The most commonly given starting point for the Middle Ages is 476, for Europe as a whole,1500 is often considered to be the end of the Middle Ages, but there is no universally agreed upon end date. English historians often use the Battle of Bosworth Field in 1485 to mark the end of the period

11.
Ferdinand Magellan
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Commanding a fleet of five vessels, he headed south through the Atlantic Ocean to Patagonia, passing through the Strait of Magellan into a body of water he named the peaceful sea. Despite a series of storms and mutinies, the reached the Spice Islands in 1521. Magellan did not complete the voyage, as he was killed during the Battle of Mactan in the Philippines in 1521. Magellan had already reached the Malay Archipelago in Southeast Asia on previous voyages traveling east, by visiting this area again but now travelling west, Magellan achieved a nearly complete personal circumnavigation of the globe for the first time in history. The Magellanic penguin is named after him, as he was the first European to note it. Magellan was born in northern Portugal in around 1480, either at Vila Nova de Gaia, near Porto, in Douro Litoral Province, or at Sabrosa, near Vila Real, in Trás-os-Montes e Alto Douro Province. He was the son of Rodrigo de Magalhães, Alcaide-Mor of Aveiro and wife Alda de Mesquita and brother of Leonor or Genebra de Magalhães, in March 1505 at the age of 25, Magellan enlisted in the fleet of 22 ships sent to host D. Francisco de Almeida as the first viceroy of Portuguese India, although his name does not appear in the chronicles, it is known that he remained there eight years, in Goa, Cochin and Quilon. He participated in battles, including the battle of Cannanore in 1506. In 1509 he fought in the battle of Diu and he later sailed under Diogo Lopes de Sequeira in the first Portuguese embassy to Malacca, with Francisco Serrão, his friend and possibly cousin. In September, after arriving at Malacca, the expedition fell victim to an ending in retreat. Magellan had a role, warning Sequeira and saving Francisco Serrão. In 1511, under the new governor Afonso de Albuquerque, Magellan, after the conquest their ways parted, Magellan was promoted, with a rich plunder and, in the company of a Malay he had indentured and baptized Enrique of Malacca, he returned to Portugal in 1512. Serrão departed in the first expedition sent to find the Spice Islands in the Moluccas and he married a woman from Amboina and became a military advisor to the Sultan of Ternate, Bayan Sirrullah. His letters to Magellan would prove decisive, giving information about the spice-producing territories, after taking a leave without permission, Magellan fell out of favour. Serving in Morocco, he was wounded, resulting in a permanent limp and he was accused of trading illegally with the Moors. The accusations were proved false, but he received no offers of employment after 15 May 1514. Later on in 1515, he got an employment offer as a member on a Portuguese ship

12.
Circumnavigation
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Circumnavigation means to travel all the way around the entire planet, or an island, or continent. This article is concerned with circumnavigation of the Earth, the first known circumnavigation of Earth was the Magellan-Elcano expedition, which sailed from Seville, Spain, in 1519 and returned in 1522 after crossing the Atlantic, Pacific and Indian oceans. The word circumnavigation is a formed from the verb circumnavigate, from the past participle of the Latin verb circumnavigare. If a person walks completely around either Pole, they cross all meridians, the trajectory of a true circumnavigation forms a continuous loop on the surface of Earth separating two halves of comparable area. A basic definition of a global circumnavigation would be a route which covers roughly a great circle, in practice, people use different definitions of world circumnavigation to accommodate practical constraints, depending on the method of travel. The first single voyage of global circumnavigation was that of the ship Victoria and it was a Castilian voyage of discovery, led initially by Ferdinand Magellan between 1519 and 1521, and then by the Basque Juan Sebastián Elcano from 1521 to 1522. It then continued across the Pacific discovering a number of islands on its way, Elcano and a small group of 18 men were actually the only members of the expedition to make the full circumnavigation. However, traveling west from Europe, in 1521, Magellan reached a region of Southeast Asia, Magellan thereby achieved a nearly complete personal circumnavigation of the globe for the first time in history. In 1577, Elizabeth I sent Francis Drake to start an expedition against the Spanish along the Pacific coast of the Americas, Drake set out from Plymouth, England in November 1577, aboard Pelican, which Drake renamed Golden Hind mid-voyage. In June 1579, Drake landed somewhere north of Spains northern-most claim in Alta California, Drake completed the second circumnavigation of the world in September 1580, becoming the first commander to lead an entire circumnavigation. For the wealthy, long voyages around the world, such as was done by Ulysses S. Grant, became possible in the 19th century, however, it was later improvements in technology and rising incomes that made such trips relatively common. The nautical global circumnavigation record is held by a wind-powered vessel. It can be seen that the route roughly approximates a great circle, in yacht racing, a round-the-world route approximating a great circle would be quite impractical, particularly in a non-stop race where use of the Panama and Suez Canals would be impossible. The second map on the shows the route of the Vendée Globe round-the-world race in red. It can be seen that the route does not pass through any pairs of antipodal points and it is allowed to have one single waypoint to lengthen the calculated track. The voyage followed the North Atlantic Ocean, Equator, South Atlantic Ocean, Southern Ocean, South Atlantic Ocean, Equator, since the advent of world cruises in 1922, by Cunards Laconia, thousands of people have completed circumnavigations of the globe at a more leisurely pace. Typically, these voyages begin in New York City or Southampton, routes vary, either travelling through the Caribbean and then into the Pacific Ocean via the Panama Canal, or around Cape Horn. From there ships usually make their way to Hawaii, the islands of the South Pacific, Australia, New Zealand, then northward to Hong Kong, South East Asia, and India

13.
Flat Earth
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The flat Earth model is an archaic conception of the Earths shape as a plane or disk. The idea of a spherical Earth appeared in Greek philosophy with Pythagoras, Aristotle provided evidence for the spherical shape of the Earth on empirical grounds by around 330 BC. Knowledge of the spherical Earth gradually began to spread beyond the Hellenistic world from then on, Modern flat Earth theories, such as those espoused by modern flat Earth societies, are commonly labelled pseudoscience. In early Egyptian and Mesopotamian thought, the world was portrayed as a disk floating in the ocean, the Israelites had a similar cosmology, with the earth as a flat disc floating on water beneath an arced firmament separating it from the heavens. Both Homer and Hesiod described a flat disc cosmography on the Shield of Achilles and this poetic tradition of an earth-encircling sea and a flat disc also appears in Stasinus of Cyprus, Mimnermus, Aeschylus, and Apollonius Rhodius. Several pre-Socratic philosophers believed that the world was flat, Thales according to several sources, Thales thought the earth floated in water like a log. It has been argued, however, that Thales actually believed in a round Earth, anaximander believed the Earth was a short cylinder with a flat, circular top that remained stable because it was the same distance from all things. Xenophanes of Colophon thought that the Earth was flat, with its upper side touching the air, belief in a flat Earth continued into the 5th century BC. Hecataeus of Miletus believed the earth was flat and surrounded by water, ancient India had a range of theories about the shape of the earth from it being a flat disc to being a spherical globe. Many of the medieval era Puranas present a flat earth cosmology. However, the disc shaped earth is not the only cosmology presented in these texts. The ancient Norse and Germanic peoples believed in a flat Earth cosmography with the Earth surrounded by an ocean, with the axis mundi, the Norse believed that in the world-encircling ocean sat a snake called Jormungandr. About her, and it may seem a hard thing to most men to cross over it. But if you take an apple and hang it close to the flame, so near that it is heated, from this you may infer that the earth-circle is round like a ball and not equally near the sun at every point. But where the surface lies nearest the suns path, there will the greatest heat be. This analogy with a curved egg led some historians, notably Joseph Needham, to conjecture that Chinese astronomers were, after all. Earth takes its body from the Yin, so it is flat, the point of the egg analogy is simply to stress that the earth is completely enclosed by heaven, rather than merely covered from above as the Kai Tian describes. Further examples cited by Needham supposed to demonstrate dissenting voices from the ancient Chinese consensus actually refer without exception to the Earth being square, not to it being flat

14.
Mesopotamian mythology
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The religious development of Mesopotamia and Mesopotamian culture in general was not particularly influenced by the movements of the various peoples into and throughout the area. Rather, Mesopotamian religion was a consistent and coherent tradition which adapted to the needs of its adherents over millenia of development. The earliest undercurrents of Mesopotamian religious thought date to the 4th millennium BCE, in the 3rd millennium BCE objects of worship were personified and became an expansive cast of divinities with particular functions. Mesopotamian religion finally declined with the spread of Iranian religions during the Achaemenid Empire, as with most dead religions, many aspects of the common practices and intricacies of the doctrine have been lost and forgotten over time. Mesopotamian religion is thought to have been an influence on subsequent religions throughout the world, including Canaanite, Aramean, Mesopotamian religion has the oldest body of recorded literature of any religious tradition. Other artifacts can also be useful when reconstructing Mesopotamian religion, as is common with most ancient civilizations, the objects made of the most durable and precious materials, and thus more likely to survive, were associated with religious beliefs and practices. It has also inspired various contemporary Neo-pagan groups, in the fourth millennium BCE, the first evidence for what is recognisably Mesopotamian religion can be seen with the invention in Mesopotamia of writing circa 3500 BCE. The people of Mesopotamia originally consisted of two groups, Akkadian speakers and the people of Sumer, who spoke a language isolate and these peoples were members of various city-states and small kingdoms. The Sumerians left the first records, although it is not known if they migrated into the area in prehistory or whether they were its original inhabitants and they resided in southern Mesopotamia, which was known as Sumer, and had considerable influence on the Akkadian speakers and their culture. Akkadian names first appear in the lists of these states circa 2800 BCE. They created the first city-states such as Uruk, Ur, Lagash, Isin, Kish, Umma, Eridu, Adab, Akshak, Sippar, Nippur and Larsa, each of them ruled by an ensí. The Akkadian Empire endured for two centuries before collapsing due to decline, internal strife and attacks from the north east by the Gutian people. Following a brief Sumerian revival with the Third Dynasty of Ur, Assyria asserted itself in the north circa 2100 BCE in the Old Assyrian Empire and southern Mesopotamia fragmented into a number of kingdoms, the largest being Isin, Larsa and Eshnunna. In 1894 BCE the initially minor city-state of Babylon was founded in the south by invading West Semitic-speaking Amorites and it was rarely ruled by native dynasties throughout its history. Some time after this period, the Sumerians disappeared, becoming absorbed into the Akkadian-speaking population. Assyrian kings are attested from the late 25th century BCE and dominated northern Mesopotamia and parts of Anatolia, the Amorite dynasty was deposed in 1595 BCE after attacks from mountain-dwelling people known as the Kassites from the Zagros Mountains, who went on to rule Babylon for over 500 years. Assyria defeated the Hittites and Mitanni, and its growing power forced the New Kingdom of Egypt to withdraw from the Near East, the Middle Assyrian Empire at its height stretched from the Caucasus to modern Bahrain and from Cyprus to western Iran. During the Neo-Assyrian Empire, Mesopotamian Aramaic became the lingua franca of the empire, the last written records in Akkadian were astrological texts dating from 78 CE discovered in Assyria

15.
Early world maps
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The earliest known world maps date to classical antiquity, the oldest examples of the 6th to 5th centuries BCE still based on the flat Earth paradigm. World maps assuming a spherical Earth first appear in the Hellenistic period, a Babylonian world map, known as the Imago Mundi, is commonly dated to the 6th century BCE. The accompanying text mentions seven outer regions beyond the encircling ocean, the descriptions of five of them have survived, the third island is where the winged bird ends not his flight, i. e. cannot reach. On the fourth island the light is brighter than that of sunset or stars, it lay in the northwest, the fifth island, due north, lay in complete darkness, a land where one sees nothing, and the sun is not visible. The sixth island, where a horned bull dwells and attacks the newcomer the seventh island lay in the east and is where the morning dawns. Anaximander is credited with having created one of the first maps of the world and this was all surrounded by the ocean. Hecataeus of Miletus is credited with a work entitled Ges Periodos, one on Europe, is essentially a periplus of the Mediterranean, describing each region in turn, reaching as far north as Scythia. The other book, on Asia, is arranged similarly to the Periplus of the Erythraean Sea of which a version of the 1st century CE survives. The work only survives in some 374 fragments, by far the majority being quoted in the geographical lexicon Ethnika compiled by Stephanus of Byzantium, Eratosthenes drew an improved world map, incorporating information from the campaigns of Alexander the Great and his successors. Asia became wider, reflecting the new understanding of the size of the continent. Eratosthenes was also the first geographer to incorporate parallels and meridians within his cartographic depictions and his work about the ocean and the adjacent areas was a general geographical discussion, showing how all the forces had an effect on each other and applied also to human life. He measured the Earths circumference by reference to the position of the star Canopus and his measure of 240,000 stadia translates to 24,000 miles, close to the actual circumference of 24,901 miles. He was informed in his approach by Eratosthenes, who a century used the elevation of the Sun at different latitudes. Both mens figures for the Earths circumference were uncannily accurate, aided in each case by mutually compensating errors in measurement, Strabo is mostly famous for his 17-volume work Geographica, which presented a descriptive history of people and places from different regions of the world known to his era. The Geographica first appeared in Western Europe in Rome as a Latin translation issued around 1469, Geographica provides a valuable source of information on the ancient world, especially when this information is corroborated by other sources. Within the books of Geographica is a map of Europe, whole world maps according to Strabo are reconstructions from his written text. Marinus of Tyres world maps were the first in the Roman Empire to show China, around 120 CE, Marinus wrote that the habitable world was bounded on the west by the Fortunate Islands. The text of his geographical treatise however is lost and he also invented the equirectangular projection, which is still used in map creation today

16.
Anaximander
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Anaximander was a pre-Socratic Greek philosopher who lived in Miletus, a city of Ionia. He belonged to the Milesian school and learned the teachings of his master Thales and he succeeded Thales and became the second master of that school where he counted Anaximenes and, arguably, Pythagoras amongst his pupils. Little of his life and work is known today, according to available historical documents, he is the first philosopher known to have written down his studies, although only one fragment of his work remains. Fragmentary testimonies found in documents after his death provide a portrait of the man, like many thinkers of his time, Anaximanders philosophy included contributions to many disciplines. In astronomy, he attempted to describe the mechanics of celestial bodies in relation to the Earth, in physics, his postulation that the indefinite was the source of all things led Greek philosophy to a new level of conceptual abstraction. His knowledge of geometry allowed him to introduce the gnomon in Greece and he created a map of the world that contributed greatly to the advancement of geography. He was also involved in the politics of Miletus and was sent as a leader to one of its colonies, Anaximander, son of Praxiades, was born in the third year of the 42nd Olympiad. According to Apollodorus of Athens, Greek grammarian of the 2nd century BC, he was years old during the second year of the 58th Olympiad. Establishing a timeline of his work is now impossible, since no document provides chronological references, Themistius, a 4th-century Byzantine rhetorician, mentions that he was the first of the known Greeks to publish a written document on nature. Therefore, his texts would be amongst the earliest written in prose, by the time of Plato, his philosophy was almost forgotten, and Aristotle, his successor Theophrastus and a few doxographers provide us with the little information that remains. However, we know from Aristotle that Thales, also from Miletus and it is debatable whether Thales actually was the teacher of Anaximander, but there is no doubt that Anaximander was influenced by Thales theory that everything is derived from water. 3rd-century Roman rhetorician Aelian depicts him as leader of the Milesian colony to Apollonia on the Black Sea coast, indeed, Various History explains that philosophers sometimes also dealt with political matters. It is very likely that leaders of Miletus sent him there as a legislator to create a constitution or simply to maintain the colony’s allegiance. Anaximanders theories were influenced by the Greek mythical tradition, and by some ideas of Thales – the father of philosophy – as well as by observations made by older civilizations in the East. This was a practice for the Greek philosophers in a society which saw gods everywhere, therefore they could fit their ideas into a tolerably elastic system. Some scholars see a gap between the mythical and the new rational way of thought which is the main characteristic of the archaic period in the Greek city states. This has given rise to the phrase Greek miracle, but if we follow carefully the course of Anaximanders ideas, we will notice that there was not such an abrupt break as initially appears. The basic elements of nature which the first Greek philosophers believed that constituted the universe represent in fact the primordial forces of previous thought and their collision produced what the mythical tradition had called cosmic harmony

17.
Hecataeus of Miletus
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Hecataeus of Miletus, son of Hagesandrus, was an early Greek historian and geographer. Hailing from a family, he lived in Miletus, then under Persian rule. He was active during the time of the Greco-Persian Wars, after having travelled extensively, he settled in his native city, where he occupied a high position, and devoted his time to the composition of geographical and historical works. When Aristagoras held a council of the leading Ionians at Miletus to organize a revolt against the Persian rule, Hecataeus tried in vain to dissuade his countrymen from the undertaking. In 494 BC, when the defeated Ionians were obliged to sue for terms, he was one of the ambassadors to the Persian satrap Artaphernes, Hecataeus is the first known Greek historian and was one of the first classical writers to mention the Celtic people. Two works by Hecateus are known, Περίοδος γῆς and Γενεαλογίαι or the Ἱστορία, however, they only survive in fragments. Periodos ges was written in two books, the first on Europe, the second on Asia, in which he included Africa. The book is a work on geography beginning at the Straits of Gibraltar and going clockwise ending at the Atlantic coast of Morocco following the coast of the Mediterranean. Over 300 fragments of this work are preserved, mostly as citations for place names in the work of Stephanus of Byzantium, Hecataeus other work was a book on mythography in four books. He applied a skeptical approach to the traditions of families who claimed to be descended from gods. One fragment that has survived is the opening Hecataeus of Miletus thus speaks, I write what I deem true, for the stories of the Greeks are manifold, Herodotus tells a story of a visit by Hecataeus to an Egyptian temple at Thebes. It recounts how the priests showed Herodotus a series of statues in the inner sanctum. Hecataeus, says Herodotus, had seen the spectacle, after mentioning that he traced his descent, through sixteen generations. Historian James Shotwell has called this encounter with the antiquity of Egypt an influence on Hecataeuss scepticism, besides his written works, Hecataeus is also credited with improving the map of Anaximander, which he saw as a disc encircled by Oceanus. Herodotus, though he once at least contradicts his statements, is indebted to Hecataeus for the concept of a prose history and this article incorporates text from a publication now in the public domain, Chisholm, Hugh, ed. Hecataeus of Miletus. Iranica, article on Hecataeus of Miletus, bibliography Hecataei Milesii Fragmenta, Scylacis Caryandensis Periplus 1831 edition of Hecateus fragments from Google Books

18.
Ziggurat
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A ziggurat was a massive structure built in ancient Mesopotamia and the western Iranian plateau. It had the form of a step pyramid of successively receding stories or levels. Notable ziggurats include the Great Ziggurat of Ur near Nasiriyah, the Ziggurat of Aqar Quf near Baghdad, Ziggurats were built by the ancient Sumerians, Babylonians, Elamites, Akkadians, and Assyrians for local religions. Each ziggurat was part of a complex which included other buildings. The precursors of the ziggurat were raised platforms that date from the Ubaid period during the fourth millennium BCE, the earliest ziggurats began as a platform, the ziggurat was a pyramidal structure with a flat top. Sun-baked bricks made up the core of the ziggurat with facings of fired bricks on the outside, each step was slightly smaller than the step below it. The facings were often glazed in different colors and may have had astrological significance, kings sometimes had their names engraved on these glazed bricks. The number of floors ranged from two to seven, according to archaeologist Harriet Crawford, It is usually assumed that the ziggurats supported a shrine, though the only evidence for this comes from Herodotus, and physical evidence is nonexistent. It has also suggested by a number of scholars that this shrine was the scene of the sacred marriage. Herodotus describes the furnishing of the shrine on top of the ziggurat at Babylon, the god Marduk was also said to come and sleep in his shrine. The likelihood of such a shrine ever being found is sadly remote, erosion has usually reduced the surviving ziggurats to a fraction of their original height, but textual evidence may yet provide more facts about the purpose of these shrines. Access to the shrine would have been by a series of ramps on one side of the ziggurat or by a ramp from base to summit. The Mesopotamian ziggurats were not places for worship or ceremonies. They were believed to be dwelling places for the gods and each city had its own patron god, only priests were permitted on the ziggurat or in the rooms at its base, and it was their responsibility to care for the gods and attend to their needs. The priests were very powerful members of Sumerian society, one of the best-preserved ziggurats is Chogha Zanbil in western Iran. The Sialk ziggurat, in Kashan, Iran, is the oldest known ziggurat, Ziggurat designs ranged from simple bases upon which a temple sat, to marvels of mathematics and construction which spanned several terraced stories and were topped with a temple. An example of a simple ziggurat is the White Temple of Uruk, the ziggurat itself is the base on which the White Temple is set. Its purpose is to get the temple closer to the heavens, the Mesopotamians believed that these pyramid temples connected heaven and earth

19.
Cosmic mountain
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The axis mundi, in certain beliefs and philosophies, is the world center, or the connection between Heaven and Earth. As the celestial pole and geographic pole, it expresses a point of connection between sky and earth where the four directions meet. At this point travel and correspondence is made higher and lower realms. Communication from lower realms may ascend to higher ones and blessings from higher realms may descend to lower ones, the spot functions as the omphalos, the worlds point of beginning. The image is viewed as feminine, as it relates to the center of the earth. It may have the form of an object or a product of human manufacture. Its proximity to heaven may carry implications that are religious or secular. The image appears in religious and secular contexts, the axis mundi symbol may be found in cultures utilizing shamanic practices or animist belief systems, in major world religions, and in technologically advanced urban centers. In Mircea Eliades opinion, Every Microcosm, every inhabited region, has a Centre, that is to say, the axis mundi is often associated with mandalas. The symbol originates in a natural and universal psychological perception, that the spot one occupies stands at the center of the world and this space serves as a microcosm of order because it is known and settled. Outside the boundaries of the microcosm lie foreign realms that, because they are unfamiliar or not ordered, represent chaos, from the center one may still venture in any of the four cardinal directions, make discoveries, and establish new centers as new realms become known and settled. Within the central known universe a specific locale-often a mountain or other elevated place, a spot where earth and sky come closest gains status as center of the center, high mountains are typically regarded as sacred by peoples living near them. Shrines are often erected at the summit or base, Mount Kunlun fills a similar role in China. For the ancient Hebrews Mount Zion expressed the symbol, sioux beliefs take the Black Hills as the axis mundi. Mount Kailash is holy to Hinduism and several religions in Tibet, the Pitjantjatjara people in central Australia consider Uluru to be central to both their world and culture. In ancient Mesopotamia the cultures of ancient Sumer and Babylon erected artificial mountains, or ziggurats and these supported staircases leading to temples at the top. The Hindu temples in India are often situated on high mountains, the pre-Columbian residents of Teotihuacán in Mexico erected huge pyramids featuring staircases leading to heaven. Jacobs Ladder is an axis mundi image, as is the Temple Mount, for Christians the Cross on Mount Calvary expresses the symbol

20.
Avesta
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The Avesta /əˈvɛstə/ is the primary collection of religious texts of Zoroastrianism, composed in the otherwise unrecorded Avestan language. The Avesta texts fall into different categories, arranged either by dialect. The principal text in the group is the Yasna, which takes its name from the Yasna ceremony, Zoroastrianisms primary act of worship. The most important portion of the Yasna texts are the five Gathas and these hymns, together with five other short Old Avestan texts that are also part of the Yasna, are in the Old Avestan language. The remainder of the Yasnas texts are in Younger Avestan, which is not only from a stage of the language. Extensions to the Yasna ceremony include the texts of the Vendidad, the Visperad extensions consist mainly of additional invocations of the divinities, while the Vendidad is a mixed collection of prose texts mostly dealing with purity laws. Even today, the Vendidad is the liturgical text that is not recited entirely from memory. Some of the materials of the extended Yasna are from the Yashts, unlike the Yasna, Visperad and Vendidad, the Yashts and the other lesser texts of the Avesta are no longer used liturgically in high rituals. Aside from the Yashts, these lesser texts include the Nyayesh texts, the Gah texts, the Siroza. Together, these texts are conventionally called Khordeh Avesta or Little Avesta texts. When the first Khordeh Avesta editions were printed in the 19th century, the term Avesta is from the 9th/10th-century works of Zoroastrian tradition in which the word appears as Zoroastrian Middle Persian abestāg, Book Pahlavi ʾpstʾkʼ. In that context, abestāg texts are portrayed as received knowledge, the literal meaning of the word abestāg is uncertain, it is generally acknowledged to be a learned borrowing from Avestan, but none of the suggested etymologies have been universally accepted. The surviving texts of the Avesta, as they exist today and that master copy, now lost, is known as the Sassanian archetype. The oldest surviving manuscript of an Avestan language text is dated 1323 CE, summaries of the various Avesta texts found in the 9th/10th century texts of Zoroastrian tradition suggest that about three-quarters of the corpus has since been lost. A pre-Sasanian history of the Avesta, if it had one, is in the realm of legend, the oldest surviving versions of these tales are found in the ninth to 11th century texts of Zoroastrian tradition. The legends run as follows, The twenty-one nasks of the Avesta were created by Ahura Mazda, supposedly, Vishtaspa or another Kayanian, Daray, then had two copies made, one of which was stored in the treasury, and the other in the royal archives. Following Alexanders conquest, the Avesta was then supposedly destroyed or dispersed by the Greeks after they translated the scientific passages that they could make use of, the Denkard also transmits another legend related to the transmission of the Avesta. In that story, credit for collation and recension is given to the early Sasanian-era priest Tansar, who had the works collected

21.
Persian Empire
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Persian Empire refers to any of a series of imperial dynasties centered in Persia. The first of these was the Achaemenid Empire established by Cyrus the Great in 550 BC with the conquest of Median, Lydian and Babylonian empires and it covered much of the Ancient world when it was conquered by Alexander the Great. Several later dynasties claimed to be heirs of the Achaemenids, Persia was then ruled by the Parthian Empire which supplanted the Hellenistic Seleucid Empire, and then by the Sassanian Empire which ruled up until mid 7th century. It is important to note that many of these empires referred to themselves as Persian, they were often ethnically ruled by Medes, Babylonians. Iranian dynastic history was interrupted by the Arab Muslim conquest of Persia in 651 AD, establishing the even larger Islamic Caliphate, the main religion of ancient Persia was the native Zoroastrianism, but after the seventh century, it was replaced by Islam. Since 1979 and the downfall of the Pahlavi dynasty during Iranian Revolution, Persia has had a Shiah theocratic government

22.
Earth ellipsoid
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An Earth ellipsoid is a mathematical figure approximating the shape of the Earth, used as a reference frame for computations in geodesy, astronomy and the geosciences. Various different ellipsoids have been used as approximations and it is an ellipsoid of revolution, whose short axis is approximately aligned with the rotation axis of the Earth. The ellipsoid is defined by the axis a and the polar axis b. Additional parameters are the mass function J2, the correspondent gravity formula, many methods exist for determination of the axes of an Earth ellipsoid, ranging from meridian arcs up to modern satellite geodesy or the analysis and interconnection of continental geodetic networks. Amongst the different set of used in national surveys are several of special importance, the Bessel ellipsoid of 1841, the international Hayford ellipsoid of 1924. A data set describes the global average of the Earths surface curvature is called the mean Earth Ellipsoid. It refers to a theoretical coherence between the latitude and the meridional curvature of the geoid. The latter is close to the sea level, and therefore an ideal Earth ellipsoid has the same volume as the geoid. While the mean Earth ellipsoid is the basis of global geodesy. Another reason is a one, the coordinates of millions of boundary stones should remain fixed for a long period. If their reference surface changes, the coordinates themselves also change, however, for international networks, GPS positioning, or astronautics, these regional reasons are less relevant. As knowledge of the Earths figure is accurate, the International Geoscientific Union IUGG usually adapts the axes of the Earth ellipsoid to the best available data. High precision land surveys can be used to determine the distance between two places at nearly the same longitude by measuring a base line and a chain of triangles. The distance Δ along the meridian from one end point to a point at the latitude as the second end point is then calculated by trigonometry. The surface distance Δ is reduced to Δ, the distance at mean sea level. The intermediate distances to points on the meridian at the same latitudes as other stations of the survey may also be calculated. The geographic latitudes of both end points, φs and φf and possibly at other points are determined by astrogeodesy, if latitudes are measured at end points only, the radius of curvature at the midpoint of the meridian arc can be calculated from R = Δ/. A second meridian arc will allow the derivation of two parameters required to specify a reference ellipsoid, longer arcs with intermediate latitude determinations can completely determine the ellipsoid

23.
Isaac Newton
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His book Philosophiæ Naturalis Principia Mathematica, first published in 1687, laid the foundations of classical mechanics. Newton also made contributions to optics, and he shares credit with Gottfried Wilhelm Leibniz for developing the infinitesimal calculus. Newtons Principia formulated the laws of motion and universal gravitation that dominated scientists view of the universe for the next three centuries. Newtons work on light was collected in his influential book Opticks. He also formulated a law of cooling, made the first theoretical calculation of the speed of sound. Newton was a fellow of Trinity College and the second Lucasian Professor of Mathematics at the University of Cambridge, politically and personally tied to the Whig party, Newton served two brief terms as Member of Parliament for the University of Cambridge, in 1689–90 and 1701–02. He was knighted by Queen Anne in 1705 and he spent the last three decades of his life in London, serving as Warden and Master of the Royal Mint and his father, also named Isaac Newton, had died three months before. Born prematurely, he was a child, his mother Hannah Ayscough reportedly said that he could have fit inside a quart mug. When Newton was three, his mother remarried and went to live with her new husband, the Reverend Barnabas Smith, leaving her son in the care of his maternal grandmother, Newtons mother had three children from her second marriage. From the age of twelve until he was seventeen, Newton was educated at The Kings School, Grantham which taught Latin and Greek. He was removed from school, and by October 1659, he was to be found at Woolsthorpe-by-Colsterworth, Henry Stokes, master at the Kings School, persuaded his mother to send him back to school so that he might complete his education. Motivated partly by a desire for revenge against a bully, he became the top-ranked student. In June 1661, he was admitted to Trinity College, Cambridge and he started as a subsizar—paying his way by performing valets duties—until he was awarded a scholarship in 1664, which guaranteed him four more years until he would get his M. A. He set down in his notebook a series of Quaestiones about mechanical philosophy as he found it, in 1665, he discovered the generalised binomial theorem and began to develop a mathematical theory that later became calculus. Soon after Newton had obtained his B. A. degree in August 1665, in April 1667, he returned to Cambridge and in October was elected as a fellow of Trinity. Fellows were required to become ordained priests, although this was not enforced in the restoration years, however, by 1675 the issue could not be avoided and by then his unconventional views stood in the way. Nevertheless, Newton managed to avoid it by means of a special permission from Charles II. A and he was elected a Fellow of the Royal Society in 1672. Newtons work has been said to distinctly advance every branch of mathematics then studied and his work on the subject usually referred to as fluxions or calculus, seen in a manuscript of October 1666, is now published among Newtons mathematical papers

24.
Jean Baptiste Joseph Delambre
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Jean Baptiste Joseph, chevalier Delambre was a French mathematician and astronomer. He was also director of the Paris Observatory, and author of books on the history of astronomy from ancient times to the 18th century. After a childhood fever, he suffered from very sensitive eyes, for fear of losing his ability to read, he devoured any book available and trained his memory. Delambres quickly achieved success in his career in astronomy, such that in 1788 and this portion of the meridian, which also passes through Paris, was to serve as the basis for the length of the quarter meridian, connecting the North Pole with the Equator. In April 1791, the academys Metric Commission confided this mission to Jean-Dominique de Cassini, Cassini was chosen to head the northern expedition but, as a royalist, he refused to serve under the revolutionary government after the arrest of King Louis XVI on his Flight to Varennes. Pierre Méchain headed the expedition, measuring from Barcelona to Rodez. The measurements were finished in 1798, the gathered data were presented to an international conference of savants in Paris the following year. After Méchains death in 1804, he was appointed director of the Paris Observatory and he was also professor of Astronomy at the Collège de France. The same year he married Elisabeth-Aglaée Leblanc de Pommard, a widow with whom he had lived already for a long time and he was a knight of the Order of Saint Michael and of the Légion dhonneur. His name is one of the 72 names inscribed on the Eiffel tower. He was elected a Foreign Honorary Member of the American Academy of Arts, Delambre died in 1822 and was interred in Père Lachaise Cemetery in Paris. The crater Delambre on the Moon is named after him,1, lxxii,556 pp.1 folded plate, vol. 2, viii,639 pp.16 folded plates, Reprinted by New York and London, Johnson Reprint Corporation,1965, with a new preface by Otto Neugebauer. Histoire de lastronomie du moyen age, Paris, Mme Ve Courcier,1819, lxxxiv,640 pp.17 folded plates. Reprinted by New York and London, Johnson Reprint Corporation,1965 OCLC647834, also reprinted by Paris, J. Gabay,2006. Histoire de lastronomie moderne, Paris, Mme Ve Courcier,1821,1, lxxxii,715 pp.9 folded plates, vol. 2,804 pp.8 folded plates, Reprinted by New York and London, Johnson Reprint Corporation,1969, with a new introduction and tables of contents by I. Also reprinted by Paris, Editions Jacques Gabay,2006 and this takes the history to the 17th century

25.
George Everest
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Colonel Sir George Everest FRS, FRAS was a Welsh surveyor and geographer, and the Surveyor General of India from 1830 through 1843. This survey was started by William Lambton in 1806 and it lasted for several decades, in 1865, Mount Everest was named in his honour in the English language, despite his objections, by the Royal Geographical Society. This enormous peak was surveyed by Radhanath Sikdar and named by Everests successor, Andrew Scott Waugh, Everest was born in Gwernvale Manor, just west of Crickhowell in Brecknockshire, Wales, in 1790, and he was baptised in Greenwich. Commissioned into the Royal Artillery, in 1818, Lt. Everest was appointed as assistant to Colonel William Lambton, on Lambtons death in 1823, Everest succeeded to the post of superintendent of the survey, and in 1830 he was appointed as the Surveyor-General of India. Everest retired in 1843 and he returned to the UK, where he became a Fellow of the Royal Society and he was dubbed a knight in 1861, and in 1862 he was elected as the vice-president of the Royal Geographical Society. Everest died in London in 1866 and is buried in St Andrews Church, Hove, Sir George had several siblings, including two younger brothers. Georges first younger brother was the Rev. Robert Everest, M. A. chaplain to the East India Company and author of A Journey Through the United States and Part of Canada. His second was the Rev. Thomas Roupell Everest, M. A. the father of Mary Everest, Sir Georges third daughter, Ethel Everest, was an associate of Emma Cons, and friend of Lilian Baylis. She provided financial support for the founding of Morley College in south London, one of Sir Georges sons, Lancelot Feilding Everest, was educated at Harrow School and Trinity College, Cambridge, and was called to the Bar by Lincolns Inn. He practised as a barrister in chambers in London and was also the author of The Law of Estoppel. Lancelots eldest son, Cyril Feilding Everest, enlisted in the Canadian Infantry on 17 November 1914 and was killed in action on 9 October 1916 at the Battle of the Somme, Sir Georges niece, Mary Everest, married mathematician George Boole in Gloucestershire on 11 September 1855. In spite of the absence of training, Mary was a fine mathematician in her own right, as was one of her daughters. Alicias son, Leonard Boole Stott, studied medicine and became a pioneer in the treatment and control of tuberculosis, Everest owned a house in Mussoorie, Uttarakhand, India, for about 11 years. He purchased it, sight unseen, from General Whish, although now virtually derelict, it still has its roof, and there have been various plans to make it into a museum. Built in 1832, the house is today as Sir George Everests House and Laboratory. The house is situated in Park Estate about 6 kilometres west of Gandhi Chowk / Library Bazaar and its location has panoramic views of the Doon Valley on one side and the Aglar River valley and the Himalayan Range to the north. The house is under the jurisdiction of the Tourism Department and these underground water cisterns are quite deep and lie uncovered in the front yard outside the house, filled with litter and posing danger of slipping. The interior has been stripped but the fireplaces, roof, the house is secured by steel grills and cannot be entered

26.
United States Department of Defense
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The Department is the largest employer in the world, with nearly 1.3 million active duty servicemen and women as of 2016. Adding to its employees are over 801,000 National Guardsmen and Reservists from the four services and it is headquartered at the Pentagon in Arlington, Virginia, just outside of Washington, D. C. The Department of Defense is headed by the Secretary of Defense, Military operations are managed by nine regional or functional Unified Combatant Commands. The Department of Defense also operates several joint services schools, including the National Defense University, the history of the defense of the United States started with the Continental Congress in 1775. The creation of the United States Army was enacted on 14 June 1775 and this coincides with the American holiday Flag Day. The Second Continental Congress would charter the United States Navy, on 13 October 1775, today, both the Navy and the Marine Corps are separate military services subordinate to the Department of the Navy. The Preamble of the United States Constitution gave the authority to federal government, to defend its citizens and this first Congress had a huge agenda, that of creating legislation to build a government for the ages. Legislation to create a military defense force stagnated, two separate times, President George Washington went to Congress to remind them of their duty to establish a military. In a special message to Congress on 19 December 1945, the President cited both wasteful military spending and inter-departmental conflicts, deliberations in Congress went on for months focusing heavily on the role of the military in society and the threat of granting too much military power to the executive. The act placed the National Military Establishment under the control of a single Secretary of Defense, the National Military Establishment formally began operations on 18 September, the day after the Senate confirmed James V. Forrestal as the first Secretary of Defense. The National Military Establishment was renamed the Department of Defense on 10 August 1949, under the Department of Defense Reorganization Act of 1958, channels of authority within the department were streamlined, while still maintaining the authority of the Military Departments. Also provided in this legislation was a centralized authority, the Advanced Research Projects Agency. The Act moved decision-making authority from the Military Departments to the Joint Chiefs of Staff and it also strengthened the command channel of the military over U. S. forces from the President to the Secretary of Defense. Written and promoted by the Eisenhower administration, it was signed into law 6 August 1958, because the Constitution vests all military authority in Congress and the President, the statutory authority of the Secretary of Defense is derived from their constitutional authorities. Department of Defense Directive 5100.01 describes the relationships within the Department. The latest version, signed by former Secretary of Defense Robert Gates in December 2010, is the first major re-write since 1987, the Office of the Secretary of Defense is the Secretary and Deputy Secretarys civilian staff. S. Government departments and agencies, foreign governments, and international organizations, OSD also performs oversight and management of the Defense Agencies and Department of Defense Field Activities. OSD also supervises the following Defense Agencies, Several defense agencies are members of the United States Intelligence Community and these are national-level intelligence services that operate under the jurisdiction of the Department of Defense but simultaneously fall under the authorities of the Director of National Intelligence

27.
World Geodetic System
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The World Geodetic System is a standard for use in cartography, geodesy, and navigation including GPS. It comprises a standard system for the Earth, a standard spheroidal reference surface for raw altitude data. The latest revision is WGS84, established in 1984 and last revised in 2004, earlier schemes included WGS72, WGS66, and WGS60. WGS84 is the coordinate system used by the Global Positioning System. The coordinate origin of WGS84 is meant to be located at the Earths center of mass, the error is believed to be less than 2 cm. The WGS84 meridian of longitude is the IERS Reference Meridian,5.31 arc seconds or 102.5 metres east of the Greenwich meridian at the latitude of the Royal Observatory. The WGS84 datum surface is a spheroid with major radius a =6378137 m at the equator. The polar semi-minor axis b then equals a times, or 6356752.3142 m, currently, WGS84 uses the EGM96 geoid, revised in 2004. This geoid defines the sea level surface by means of a spherical harmonics series of degree 360. The deviations of the EGM96 geoid from the WGS84 reference ellipsoid range from about −105 m to about +85 m, EGM96 differs from the original WGS84 geoid, referred to as EGM84. Efforts to supplement the national surveying systems began in the 19th century with F. R. Helmerts famous book Mathematische und Physikalische Theorien der Physikalischen Geodäsie. Austria and Germany founded the Zentralbüro für die Internationale Erdmessung, a unified geodetic system for the whole world became essential in the 1950s for several reasons, International space science and the beginning of astronautics. The lack of inter-continental geodetic information, efforts of the U. S. Army, Navy and Air Force were combined leading to the DoD World Geodetic System 1960. Heritage surveying methods found elevation differences from a local horizontal determined by the level, plumb line. As a result, the elevations in the data are referenced to the geoid, the latter observational method is more suitable for global mapping. The sole contribution of data to the development of WGS60 was a value for the ellipsoid flattening which was obtained from the nodal motion of a satellite. Prior to WGS60, the U. S. Army, the Army performed an adjustment to minimize the difference between astro-geodetic and gravimetric geoids. By matching the relative astro-geodetic geoids of the selected datums with an earth-centered gravimetric geoid, since the Army and Air Force systems agreed remarkably well for the NAD, ED and TD areas, they were consolidated and became WGS60

28.
Altitude
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Altitude or height is defined based on the context in which it is used. As a general definition, altitude is a measurement, usually in the vertical or up direction. The reference datum also often varies according to the context, although the term altitude is commonly used to mean the height above sea level of a location, in geography the term elevation is often preferred for this usage. Vertical distance measurements in the direction are commonly referred to as depth. In aviation, the altitude can have several meanings, and is always qualified by explicitly adding a modifier. Parties exchanging altitude information must be clear which definition is being used, aviation altitude is measured using either mean sea level or local ground level as the reference datum. When flying at a level, the altimeter is always set to standard pressure. On the flight deck, the instrument for measuring altitude is the pressure altimeter. There are several types of altitude, Indicated altitude is the reading on the altimeter when it is set to the local barometric pressure at mean sea level. In UK aviation radiotelephony usage, the distance of a level, a point or an object considered as a point, measured from mean sea level. Absolute altitude is the height of the aircraft above the terrain over which it is flying and it can be measured using a radar altimeter. Also referred to as radar height or feet/metres above ground level, true altitude is the actual elevation above mean sea level. It is indicated altitude corrected for temperature and pressure. Height is the elevation above a reference point, commonly the terrain elevation. Pressure altitude is used to indicate flight level which is the standard for reporting in the U. S. in Class A airspace. Pressure altitude and indicated altitude are the same when the setting is 29.92 Hg or 1013.25 millibars. Density altitude is the altitude corrected for non-ISA International Standard Atmosphere atmospheric conditions, aircraft performance depends on density altitude, which is affected by barometric pressure, humidity and temperature. On a very hot day, density altitude at an airport may be so high as to preclude takeoff and these types of altitude can be explained more simply as various ways of measuring the altitude, Indicated altitude – the altitude shown on the altimeter

29.
Greek colonies
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Colonies in antiquity were city-states founded from a mother-city, not from a territory-at-large. Bonds between a colony and its metropolis remained often close, and took specific forms, however, unlike in the period of European colonialism during the early and late modern era, ancient colonies were usually sovereign and self-governing from their inception. An Egyptian colony that was stationed in southern Canaan dates to slightly before the First Dynasty, narmer had Egyptian pottery produced in Canaan and exported back to Egypt, from regions such as Arad, En Besor, Rafiah, and Tel ʿErani. Shipbuilding was known to the ancient Egyptians as early as 3000 BC, the Archaeological Institute of America reports that the earliest dated ship—75 feet long, dating to 3000 BC – may have possibly belonged to Pharaoh Aha. Egypt at its height controlled Crete across the Mediterranean Sea, the Phoenicians were the major trading power in the Mediterranean in the early part of the first millennium BC. They had trading contacts in Egypt and Greece, and established colonies as far west as modern Spain, from Gadir the Phoenicians controlled access to the Atlantic Ocean and the trade routes to Britain. The most famous and successful of Phoenician colonies was founded by settlers from Tyre in 814–813 BC and called Kart-Hadasht (Qart-ḥadašt, the Carthaginians later founded their own colony in the southeast of Spain, Carthago Nova, which was eventually conquered by their enemy, Rome. But in most cases the motivation was to establish and facilitate relations of trade with foreign countries, colonies were established in Ionia and Thrace as early as the 8th century BC. There were two types of colony, one known as an ἀποικία - apoikia and the other as an ἐμπορίov - emporion. The first type of colony was a city-state on its own, through this Greek expansion the use of coins flourished throughout the Mediterranean Basin. The Greeks also colonised modern-day Crimea on the Black Sea, among the settlements they established there was the city of Chersonesos, at the site of modern-day Sevastopol. Another area with significant Greek colonies was the coast of ancient Illyria on the Adriatic Sea, the extensive Greek colonization is remarked upon by Cicero when noting that It were as though a Greek fringe has been woven about the shores of the barbarians. Several formulae were generally adhered to on the solemn and sacred occasions when a new colony set forth, if a Greek city was sending out a colony, an oracle, especially one such as the Oracle of Delphi, was almost invariably consulted beforehand. A person of distinction was selected to guide the emigrants and make the necessary arrangements and it was usual to honor these founders of colonies, after their death, as heroes. Some of the fire was taken from the public hearth in the Prytaneum. After the conquests of the Macedonian Kingdom and Alexander the Great, the relation between colony and mother-city, known literally as the metropolis, was viewed as one of mutual affection. Any differences that arose were resolved by peaceful means whenever possible and it is worth noting that the Peloponnesian War was in part a result of a dispute between Corinth and her colony of Corcyra. The charter of foundation contained general provisions for the arrangement of the affairs of the colony, the constitution of the mother-city was usually adopted by the colony, but the new city remained politically independent

30.
Mediterranean Sea
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The sea is sometimes considered a part of the Atlantic Ocean, although it is usually identified as a separate body of water. The name Mediterranean is derived from the Latin mediterraneus, meaning inland or in the middle of land and it covers an approximate area of 2.5 million km2, but its connection to the Atlantic is only 14 km wide. The Strait of Gibraltar is a strait that connects the Atlantic Ocean to the Mediterranean Sea and separates Gibraltar. In oceanography, it is called the Eurafrican Mediterranean Sea or the European Mediterranean Sea to distinguish it from mediterranean seas elsewhere. The Mediterranean Sea has a depth of 1,500 m. The sea is bordered on the north by Europe, the east by Asia and it is located between latitudes 30° and 46° N and longitudes 6° W and 36° E. Its west-east length, from the Strait of Gibraltar to the Gulf of Iskenderun, the seas average north-south length, from Croatia’s southern shore to Libya, is approximately 800 km. The Mediterranean Sea, including the Sea of Marmara, has an area of approximately 2,510,000 square km. The sea was an important route for merchants and travelers of ancient times that allowed for trade, the history of the Mediterranean region is crucial to understanding the origins and development of many modern societies. In addition, the Gaza Strip and the British Overseas Territories of Gibraltar and Akrotiri, the term Mediterranean derives from the Latin word mediterraneus, meaning amid the earth or between land, as it is between the continents of Africa, Asia and Europe. The Ancient Greek name Mesogeios, is similarly from μέσο, between + γη, land, earth) and it can be compared with the Ancient Greek name Mesopotamia, meaning between rivers. The Mediterranean Sea has historically had several names, for example, the Carthaginians called it the Syrian Sea and latter Romans commonly called it Mare Nostrum, and occasionally Mare Internum. Another name was the Sea of the Philistines, from the people inhabiting a large portion of its shores near the Israelites, the sea is also called the Great Sea in the General Prologue by Geoffrey Chaucer. In Ottoman Turkish, it has also been called Bahr-i Sefid, in Modern Hebrew, it has been called HaYam HaTikhon, the Middle Sea, reflecting the Seas name in ancient Greek, Latin, and modern languages in both Europe and the Middle East. Similarly, in Modern Arabic, it is known as al-Baḥr al-Mutawassiṭ, in Turkish, it is known as Akdeniz, the White Sea since among Turks the white colour represents the west. Several ancient civilisations were located around the Mediterranean shores, and were influenced by their proximity to the sea. It provided routes for trade, colonisation, and war, as well as food for numerous communities throughout the ages, due to the shared climate, geology, and access to the sea, cultures centered on the Mediterranean tended to have some extent of intertwined culture and history. Two of the most notable Mediterranean civilisations in classical antiquity were the Greek city states, later, when Augustus founded the Roman Empire, the Romans referred to the Mediterranean as Mare Nostrum

31.
Nile Delta
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The Nile Delta is the delta formed in Northern Egypt where the Nile River spreads out and drains into the Mediterranean Sea. It is one of the worlds largest river deltas—from Alexandria in the west to Port Said in the east, from north to south the delta is approximately 160 kilometres in length. The Delta begins slightly down-river from Cairo, from north to south, the delta is approximately 160 kilometres in length. From west-to-east, it covers some 240 kilometres of coastline, the delta is sometimes divided into sections, with the Nile dividing into two main distributaries, the Damietta and the Rosetta, flowing into the Mediterranean at port cities with the same name. In the past, the delta had several distributaries, but these have been lost due to flood control, one such defunct distributary is Wadi Tumilat. The Suez Canal runs to the east of the delta, entering the coastal Lake Manzala in the north-east of the delta, to the north-west are three other coastal lakes or lagoons, Lake Burullus, Lake Idku and Lake Maryut. The Nile is considered to be a delta, as it resembles a triangle or flower when seen from above. The outer edges of the delta are eroding, and some coastal lagoons have seen increasing salinity levels as their connection to the Mediterranean Sea increases, topsoil in the delta can be as much as 70 feet in depth. People have lived in the Delta region for thousands of years, the Delta River used to flood on an annual basis, but this ended with the construction of the Aswan Dam. The Rosetta Stone was found in the Nile Delta in 1799 in the city of Rosetta. The delta was a constituent of Lower Egypt. The Biblical Land of Goshen was located in an area on the west bank of the Pelusiac distributary. There are many sites in and around the Nile Delta. About 39 million people live in the Delta region, outside of major cities, population density in the delta averages 1,000 persons/km² or more. Alexandria is the largest city in the delta with a population of more than 4.5 million. Other large cities in the delta include Shubra al Khaymah, Port Said, El-Mahalla El-Kubra, El Mansura, Tanta, during autumn, parts of the Nile River are red with lotus flowers. The Lower Nile and the Upper Nile have plants that grow in abundance, the Upper Nile plant is the Egyptian lotus, and the Lower Nile plant is the Papyrus Sedge, although it is not nearly as plentiful as it once was, and is becoming quite rare. Several hundred thousand birds winter in the delta, including the world’s largest concentrations of little gulls

32.
Crimea
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The peninsula is located south of the Ukrainian region of Kherson and west of the Russian region of Kuban. It is connected to Kherson Oblast by the Isthmus of Perekop and is separated from Kuban by the Strait of Kerch, the Arabat Spit is located to the northeast, a narrow strip of land that separates a system of lagoons named Sivash from the Sea of Azov. Crimea has historically been at the boundary between the world and the Pontic–Caspian steppe. Crimea and adjacent territories were united in the Crimean Khanate during the 15th to 18th century, in 1783, Crimea was annexed by the Russian Empire. It became the Autonomous Republic of Crimea within newly independent Ukraine in 1991, with Sevastopol having its own administration, within Ukraine, since 1997, after the Peace and Friendship Treaty signed by Russia and Ukraine, Crimea hosts the Russian Black Sea Fleet naval base in Sevastopol. The ex-Soviet Black Sea Fleet and its facilities were divided between Russias Black Sea Fleet and the Ukrainian Naval Forces, the two navies shared some of the citys harbours and piers, while others were demilitarised or used by either country. Sevastopol remained the location of the Russian Black Sea Fleet headquarters with the Ukrainian Naval Forces Headquarters also based in the city, most of the international community does not recognize the annexation and considers Crimea to be Ukrainian territory. Russia currently administers the peninsula as two federal subjects, the Republic of Crimea and the city of Sevastopol. Ukraine continues to assert its right over the peninsula, the classical name Tauris or Taurica is from the Greek Ταυρική, after the peninsulas Scytho-Cimmerian inhabitants, the Tauri. In English usage since the modern period the Crimean Khanate is referred to as Crim Tartary. The Italian form Crimea also becomes current during the 18th century, the omission of the definite article in English became common during the later 20th century. The name Crimea follows the Italian form from the Crimean Tatar name for the city Qırım which served as a capital of the Crimean province of the Golden Horde, the name of the capital was extended to the entire peninsula at some point during Ottoman suzerainty. The origin of the word Qırım is uncertain, suggestions argued in various sources include, a corruption of Cimmerium. A derivation from the Turkic term qirum, from qori-, other suggestions that have not been supported by sources but are apparently based on similarity in sound include, a derivation from the Greek Cremnoi. However, he identifies the port, not in Crimea, no evidence has been identified that this name was ever in use for the peninsula. The classical name was revived in 1802 in the name of the Russian Taurida Governorate, in the 8th century BCE the Cimmerians migrated to the region and subsequently the Scythians as well it being the site of Greek colonies. The most important city was Chersonesos at the edge of todays Sevastopol, the Persian Achaemenid Empire expanded to Crimea. Later occupiers included the Romans, Goths, Huns, Bulgars, the Byzantine Empire, Khazars, the Kipchaks, the Golden Horde, consideration of the succeeding residents of the peninsula by their linguistic grouping is also of relevance

33.
Herodotus
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Herodotus was a Greek historian who was born in Halicarnassus in the Persian Empire and lived in the fifth century BC, a contemporary of Socrates. The Histories is the work which he is known to have produced. Despite Herodotus historical significance, little is known of his personal life and his place in history and his significance may be understood according to the traditions within which he worked. His work is the earliest Greek prose to have survived intact, of these only fragments of Hecataeuss work survive yet they allow us glimpses into the kind of tradition within which Herodotus wrote his own Histories. In his introduction to Hecataeus’s work, Genealogies, This points forward to the ‘folksy’ yet ‘international’ outlook typical of Herodotus. Yet, one scholar has described the work of Hecataeus as “a curious false start to history” since despite his critical spirit. It is possible that Herodotus borrowed much material from Hecataeus, as stated by Porphyry in a recorded by Eusebius. But Hecataeus did not record events that had occurred in living memory, unlike Herodotus, Herodotus claims to be better informed than his predecessors by relying on empirical observation to correct their excessive schematism. For example, He argues for continental asymmetry as opposed to the theory of a perfectly circular earth with Europe. Yet, he retains idealizing tendencies, as in his notions of the Danube. His debt to previous authors of prose ‘histories’ might be questionable, however, this point is one of the most contentious issues in modern scholarship. It is on account of the strange stories and the folk-tales he reported that his critics in early modern times branded him “The Father of Lies”. Even his own contemporaries found reason to scoff at his achievement, similarly, the Athenian historian Thucydides dismissed Herodotus as a “logos-writer”. Moreover, Thucydides developed a historical topic more in keeping with the Greek world-view, the interplay of civilizations was more relevant to Greeks living in Anatolia, such as Herodotus himself, for whom life within a foreign civilization was a recent memory. Modern scholars generally turn to Herodotus’s own writing for reliable information about his life, supplemented with ancient yet much later sources, modern accounts of his life typically go something like this, Herodotus was born at Halicarnassus around 484 BC. His name is not mentioned later in the tribute list of the Athenian Delian League, the epic poet Panyassis – a relative of Herodotus – is reported to have taken part in a failed uprising. Herodotus expresses affection for the island of Samos, and this is an indication that he might have lived there in his youth. So it is possible that his family was involved in an uprising against Lygdamis, leading to a period of exile on Samos, Herodotus wrote his Histories in the Ionian dialect, yet he was born in Halicarnassus, which was a Dorian settlement

34.
Africa
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Africa is the worlds second-largest and second-most-populous continent. At about 30.3 million km² including adjacent islands, it covers 6% of Earths total surface area and 20.4 % of its land area. With 1.2 billion people as of 2016, it accounts for about 16% of the human population. The continent includes Madagascar and various archipelagos and it contains 54 fully recognized sovereign states, nine territories and two de facto independent states with limited or no recognition. Africas population is the youngest amongst all the continents, the age in 2012 was 19.7. Algeria is Africas largest country by area, and Nigeria by population, afarensis, Homo erectus, H. habilis and H. ergaster – with the earliest Homo sapiens found in Ethiopia being dated to circa 200,000 years ago. Africa straddles the equator and encompasses numerous climate areas, it is the continent to stretch from the northern temperate to southern temperate zones. Africa hosts a diversity of ethnicities, cultures and languages. In the late 19th century European countries colonized most of Africa, Africa also varies greatly with regard to environments, economics, historical ties and government systems. However, most present states in Africa originate from a process of decolonization in the 20th century, afri was a Latin name used to refer to the inhabitants of Africa, which in its widest sense referred to all lands south of the Mediterranean. This name seems to have referred to a native Libyan tribe. The name is connected with Hebrew or Phoenician ʿafar dust. The same word may be found in the name of the Banu Ifran from Algeria and Tripolitania, under Roman rule, Carthage became the capital of the province of Africa Proconsularis, which also included the coastal part of modern Libya. The Latin suffix -ica can sometimes be used to denote a land, the later Muslim kingdom of Ifriqiya, modern-day Tunisia, also preserved a form of the name. According to the Romans, Africa lay to the west of Egypt, while Asia was used to refer to Anatolia, as Europeans came to understand the real extent of the continent, the idea of Africa expanded with their knowledge. 25,4, whose descendants, he claimed, had invaded Libya, isidore of Seville in Etymologiae XIV.5.2. Suggests Africa comes from the Latin aprica, meaning sunny, massey, in 1881, stated that Africa is derived from the Egyptian af-rui-ka, meaning to turn toward the opening of the Ka. The Ka is the double of every person and the opening of the Ka refers to a womb or birthplace

35.
Phoenicia
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The enterprising, sea-based Phoenician civilization spread across the Mediterranean between 1500 BC and 300 BC. Their civilization was organized in city-states, similar to those of Ancient Greece, perhaps the most notable of which were Tyre, Sidon, Arvad, Berytus and Carthage. Each city-state was an independent unit, and it is uncertain to what extent the Phoenicians viewed themselves as a single nationality. In terms of archaeology, language, lifestyle, and religion there was little to set the Phoenicians apart as markedly different from other Semitic Canaanites. The Phoenicians were the first state-level society to make use of alphabets. By their maritime trade, the Phoenicians spread the use of the alphabet to Anatolia, North Africa, and Europe, where it was adopted by the Greeks, the name Phoenicians, like Latin Poenī, comes from Greek Φοίνικες. The word φοῖνιξ phoînix meant variably Phoenician person, Tyrian purple, the word may be derived from φοινός phoinós blood red, itself possibly related to φόνος phónos murder. Beekes has suggested a Pre-Greek origin of the ethnonym, the oldest attested form of the word in Greek may be the Mycenaean po-ni-ki-jo, po-ni-ki, possibly borrowed from Ancient Egyptian fnḫw Asiatics, Semites, although this derivation is disputed. The folk-etymological association of Φοινίκη with φοῖνιξ mirrors that in Akkadian which tied kinaḫni, the land was natively known as knʿn and its people as the knʿny. In the Amarna tablets of the 14th century BC, people from the region called themselves Kenaani or Kinaani, the ethnonym survived in North Africa until the 4th century AD. Herodotus account refers to the myths of Io and Europa, according to the Persians best informed in history, the Phoenicians began the quarrel. The Greek historian Strabo believed that the Phoenicians originated from Bahrain, Herodotus also believed that the homeland of the Phoenicians was Bahrain. The people of Tyre in South Lebanon in particular have long maintained Persian Gulf origins, however, there is little evidence of occupation at all in Bahrain during the time when such migration had supposedly taken place. Canaanite culture apparently developed in situ from the earlier Ghassulian chalcolithic culture, Byblos is attested as an archaeological site from the Early Bronze Age. The Late Bronze Age state of Ugarit is considered quintessentially Canaanite archaeologically, fernand Braudel remarked in The Perspective of the World that Phoenicia was an early example of a world-economy surrounded by empires. The high point of Phoenician culture and sea power is usually placed c, archaeological evidence consistent with this understanding has been difficult to identify. A unique concentration in Phoenicia of silver hoards dated between 1200 and 800 BC, however, contains hacksilver with lead isotope ratios matching ores in Sardinia and Spain. This metallic evidence agrees with the memory of a western Mediterranean Tarshish that supplied Solomon with silver via Phoenicia

36.
Ancient Egypt
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Ancient Egypt was a civilization of ancient Northeastern Africa, concentrated along the lower reaches of the Nile River in what is now the modern country of Egypt. It is one of six civilizations to arise independently, Egyptian civilization followed prehistoric Egypt and coalesced around 3150 BC with the political unification of Upper and Lower Egypt under the first pharaoh Narmer. In the aftermath of Alexander the Greats death, one of his generals, Ptolemy Soter and this Greek Ptolemaic Kingdom ruled Egypt until 30 BC, when, under Cleopatra, it fell to the Roman Empire and became a Roman province. The success of ancient Egyptian civilization came partly from its ability to adapt to the conditions of the Nile River valley for agriculture, the predictable flooding and controlled irrigation of the fertile valley produced surplus crops, which supported a more dense population, and social development and culture. Its art and architecture were widely copied, and its antiquities carried off to far corners of the world and its monumental ruins have inspired the imaginations of travelers and writers for centuries. The Nile has been the lifeline of its region for much of human history, nomadic modern human hunter-gatherers began living in the Nile valley through the end of the Middle Pleistocene some 120,000 years ago. By the late Paleolithic period, the climate of Northern Africa became increasingly hot and dry. In Predynastic and Early Dynastic times, the Egyptian climate was less arid than it is today. Large regions of Egypt were covered in treed savanna and traversed by herds of grazing ungulates, foliage and fauna were far more prolific in all environs and the Nile region supported large populations of waterfowl. Hunting would have been common for Egyptians, and this is also the period when many animals were first domesticated. The largest of these cultures in upper Egypt was the Badari, which probably originated in the Western Desert, it was known for its high quality ceramics, stone tools. The Badari was followed by the Amratian and Gerzeh cultures, which brought a number of technological improvements, as early as the Naqada I Period, predynastic Egyptians imported obsidian from Ethiopia, used to shape blades and other objects from flakes. In Naqada II times, early evidence exists of contact with the Near East, particularly Canaan, establishing a power center at Hierakonpolis, and later at Abydos, Naqada III leaders expanded their control of Egypt northwards along the Nile. They also traded with Nubia to the south, the oases of the desert to the west. Royal Nubian burials at Qustul produced artifacts bearing the oldest-known examples of Egyptian dynastic symbols, such as the crown of Egypt. They also developed a ceramic glaze known as faience, which was used well into the Roman Period to decorate cups, amulets, and figurines. During the last predynastic phase, the Naqada culture began using written symbols that eventually were developed into a system of hieroglyphs for writing the ancient Egyptian language. The Early Dynastic Period was approximately contemporary to the early Sumerian-Akkadian civilisation of Mesopotamia, the third-century BC Egyptian priest Manetho grouped the long line of pharaohs from Menes to his own time into 30 dynasties, a system still used today

37.
Pharaoh
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The word pharaoh ultimately derive from the Egyptian compound pr-ˤ3 great house, written with the two biliteral hieroglyphs pr house and ˤ3 column, here meaning great or high. It was used only in larger phrases such as smr pr-ˤ3 Courtier of the High House, with specific reference to the buildings of the court or palace. From the twelfth dynasty onward, the word appears in a wish formula Great House, may it live, prosper, and be in health, but again only with reference to the royal palace and not the person. During the reign of Thutmose III in the New Kingdom, after the rule of the Hyksos during the Second Intermediate Period. During the eighteenth dynasty the title pharaoh was employed as a designation of the ruler. From the nineteenth dynasty onward pr-ˤ3 on its own was used as regularly as hm. f, the term, therefore, evolved from a word specifically referring to a building to a respectful designation for the ruler, particularly by the twenty-second dynasty and twenty-third dynasty. For instance, the first dated appearance of the pharaoh being attached to a rulers name occurs in Year 17 of Siamun on a fragment from the Karnak Priestly Annals. Here, an induction of an individual to the Amun priesthood is dated specifically to the reign of Pharaoh Siamun and this new practice was continued under his successor Psusennes II and the twenty-second dynasty kings. Shoshenq I was the successor of Siamun. Meanwhile, the old custom of referring to the sovereign simply as pr-ˤ3 continued in traditional Egyptian narratives, by this time, the Late Egyptian word is reconstructed to have been pronounced *par-ʕoʔ whence Herodotus derived the name of one of the Egyptian kings, Φερων. In the Bible, the title also occurs as פרעה, from that, Septuagint φαραώ pharaō and then Late Latin pharaō, both -n stem nouns. The Quran likewise spells it فرعون firawn with n, interestingly, the Arabic combines the original pharyngeal ayin sound from Egyptian, along with the -n ending from Greek. English at first spelt it Pharao, but the King James Bible revived Pharaoh with h from the Hebrew, meanwhile in Egypt itself, *par-ʕoʔ evolved into Sahidic Coptic ⲡⲣ̅ⲣⲟ prro and then rro. Scepters and staves were a sign of authority in ancient Egypt. One of the earliest royal scepters was discovered in the tomb of Khasekhemwy in Abydos, kings were also known to carry a staff, and Pharaoh Anedjib is shown on stone vessels carrying a so-called mks-staff. The scepter with the longest history seems to be the heqa-scepter, the earliest examples of this piece of regalia dates to pre-dynastic times. A scepter was found in a tomb at Abydos that dates to the late Naqada period, another scepter associated with the king is the was-scepter. This is a long staff mounted with an animal head, the earliest known depictions of the was-scepter date to the first dynasty

38.
Necho II
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Necho II of Egypt was a king of the 26th Dynasty. Necho undertook a number of projects across his kingdom. In his reign, according to the Greek historian Herodotus, Necho II sent out an expedition of Phoenicians and his son, Psammetichus II, upon succession may have removed Nechos name from monuments. Necho played a significant role in the histories of the Neo-Assyrian Empire, the Neo-Babylonian Empire, Necho II is most likely the pharaoh mentioned in several books of the Bible. The aim of the second of Nechos campaigns was Asiatic conquest, to contain the Westward advance of the Neo-Babylonian Empire, however, the Egyptians were defeated by the unexpected attack of the Babylonians and were eventually expelled from Syria. Necho II was the son of Psammetichus I by his Great Royal Wife Mehtenweskhet and his prenomen or royal name Wahem-Ib-Re means Carrying out Heart Re. That once mighty empire was now reduced to the troops, officials, and nobles who had gathered around a general holding out at Harran, who had taken the throne name of Ashur-uballit II. Necho attempted to assist this remnant immediately upon his coronation, but the force he sent proved to be too small, in the spring of 609 BC, Necho personally led a sizable force to help the Assyrians. He prepared to cross the ridge of hills which shuts in on the south the great Jezreel Valley and their king, Josiah, sided with the Babylonians and attempted to block his advance at Megiddo, where a fierce battle was fought and Josiah was killed. Although Necho became the first pharaoh to cross the Euphrates since Thutmose III, he failed to capture Harran, at this point, Ashur-uballit vanished from history, and the Assyrian Empire was conquered by the Babylonians. The Book of Kings states that Necho met King Josiah of the Kingdom of Judah at Megiddo, leaving a sizable force behind, Necho returned to Egypt. On his return march, he found that the Judeans had selected Jehoahaz to succeed his father Josiah and he brought Jehoahaz back to Egypt as his prisoner, where Jehoahaz ended his days. The Book of Chronicles gives an account of his death and he was then brought back to Jerusalem to die. Necho is quoted as saying, What quarrel is there between you and me, O king of Judah and it is not you I am attacking at this time, but the house with which I am at war. God has told me to hurry, so stop opposing God, the Babylonian king was planning on reasserting his power in Syria. In 609 BC, King Nabopolassar captured Kumukh, which cut off the Egyptian army, Necho responded the following year by retaking Kumukh after a four-month siege, and executed the Babylonian garrison. Nabopolassar gathered another army, which camped at Qurumati on the Euphrates, however, Nabopolassars poor health forced him to return to Babylon in 605 BC. In response, in 606 BC the Egyptians attacked the leaderless Babylonians who fled their position, although Nebuchadnezzar spent many years in his new conquests on continuous pacification campaigns, Necho was unable to recover any significant part of his lost territories

39.
Hebrew Bible
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They are composed mainly in Biblical Hebrew, with some passages in Biblical Aramaic. The term does not comment upon the naming, numbering or ordering of books, the term Hebrew Bible is an attempt to provide specificity with respect to contents but avoid allusion to any particular interpretative tradition or theological school of thought. Hebrew Bible refers to the Jewish biblical canon, in its Latin form, Biblia Hebraica, it traditionally serves as a title for printed editions of the Masoretic Text. Many biblical studies scholars advocate use of the term Hebrew Bible as a substitute to terms with religious connotations. Hebrew Bible Old Testament without prescribing the use of either, however, he accepts that there is no reason why non-Christians should feel obliged to refer to these books as the Old Testament, apart from custom of use. Modern Christian formulations of this tension include Supersessionism, Covenant Theology, New Covenant Theology, Dispensationalism, in terms of canon, Christian usage of Old Testament does not refer to a universally agreed upon set of books but, rather, varies depending on denomination. The Hebrew Bible includes small portions in Aramaic, written and printed in Aramaic square-script, the books that constitute the Hebrew Bible developed over roughly a millennium. The oldest texts seem to come from the 11th or 10th centuries BCE and they are edited works, being collections of various sources intricately and carefully woven together. Since the 19th century, most biblical scholars have agreed that the Pentateuch consists of four sources which have been woven together and these four sources are J, D, E and P sources. They were combined to form the Pentateuch sometime in the 6th century BCE and this theory is now known as the documentary hypothesis, and has been the dominant theory for the past two hundred years. The Deuteronomist credited with the Pentateuchs book of Deuteronomy is also said to be the source of the books of Joshua, Judges, Samuel, several editions, all titled Biblia Hebraica, have been produced by various German publishers since 1906. Between 1906 and 1955, Rudolf Kittel published nine editions of it,1966, the Deutsche Bibelgesellschaft published the renamed Biblia Hebraica Stuttgartensia in six editions until 1997. Since 2004 the Deutsche Bibelgesellschaft has published the Biblia Hebraica Quinta, other projects include, Hebrew University Bible Project Hebrew Bible, A Critical Edition Biblical canon Books of the Bible Non-canonical books referenced in the Bible Torah Brueggemann, Walter. An introduction to the Old Testament, the canon and Christian imagination, the People of Ancient Israel, an introduction to Old Testament Literature, History, and Thought, Harper and Row,1974. Sinai and Zion, An Entry into the Jewish Bible, archived from the original on 14 March 2012. The Ancient Near East, Volume I, Princeton, New Jersey, Princeton University Press. An abridgement of Ancient Near Eastern Texts Relating to the Old Testament Noth, how the Bible Became a Book. The Old Testament, A Literary History, hebrew-English Tanakh, the Jewish Bible Complete, fully vocalized, contilated, Masoretic text of the Hebrew Bible, together with the classic English translation by the Jewish Publication Society

40.
Shamayim
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Shamayim, the Hebrew word for heaven, denotes one component of the three-part cosmos, the other elements being erets and sheol. The Hebrew word shamayim is constructed of two parts, sham derived from Akkadian samu meaning sky or lofty, and Hebrew mayim meaning water, in Genesis 1,6 Elohim separated the water from the water. The area above the earth was filled by sky-water and the earth below was covered by sea-water, the Hebrew word for the sun is shemesh. It follows the construction, where shem or sham means sky and esh means fire. The Biblical authors pictured the earth as a disk floating in water, with the heavens above. The raqiya, an inverted bowl above the earth, coloured blue by the cosmic ocean. Biblical cosmology Celestial spheres Garden of Eden Gehenna Jannah Religious cosmology Aune, Westminster Dictionary of the New Testament and Early Christian Literature. The Westminster theological wordbook of the Bible, heaven and earth in the Gospel of Matthew

41.
Sheol
–
The inhabitants of Sheol are the shades, entities without personality or strength. Under some circumstances they are thought to be able to be contacted by the living, as the Witch of Endor contacts the shade of Samuel for Saul, but such practices are forbidden. While the Old Testament writings appear to describe Sheol as the permanent place of the dead, brichto, writing in Hebrew Union College Annual, the family tomb is the central concept in understanding biblical views of the afterlife. Although not well defined in the Tanakh, Sheol in this view was an underworld where the souls of the dead went after the body died. The Babylonians had a similar underworld called Aralu, and the Greeks had one known as Hades. For biblical references to Sheol see Genesis 42,38, Isaiah 14,11, Psalm 141,7, Daniel 12,2, Proverbs 7,27 and Job 10,21,22, the Hebrew Scriptures themselves have few references to existence after death. The notion of resurrection appears in two late biblical sources, Daniel 12 and Isaiah 25-26, the traditional biblical interpretations explain that Sheol is a grim and desolated land below, occupied by the dead who continue their colorless existence irrespective of their earthly conduct. Contrary to this however, the Hebrew Bible supports the descriptions of Sheol which suggest that it is something more than just a place. In terms of numbers the amount of anthropomorphic descriptions is significant. Sheol is either portrayed by means of human qualities or attributed with the elements of anatomy, womb, hand. Some additional support for this comes from the ancient Near Eastern literary materials. For example, the Akkadian plates mention the name shuwalu or suwala in reference to a deity responsible for ruling the abode of the dead, as such it might have been borrowed by the Hebrews and incorporated into their early belief system. What is more, some argue that Sheol understood anthropomorphically fits the semantic complex of the other ancient Near Eastern death deities such as Nergal, Ereshkigal or Mot. Barzakh Biblical cosmology Christian views on Hades Gehenna Hellenistic Judaism Limbo of the Patriarchs Spirit world Tartarus Aune, Westminster Dictionary of the New Testament and Early Christian Literature. The Formation of Hell, Death and Retribution in the Ancient, hess, Richard S. Israelite Religions, An Archeological and Biblical Survey. Hell with Purgatory and two Limbos, Hell and Its Afterlife, Historical and Contemporary Perspectives. The Oxford Dictionary of the Jewish Religion, the Westminster Theological Wordbook of the Bible. In Metzger, Bruce Manning, Coogan, Michael David, the Oxford Guide to Ideas & Issues of the Bible

42.
Pythagoras
–
Pythagoras of Samos was an Ionian Greek philosopher, mathematician, and the putative founder of the movement called Pythagoreanism. Most of the information about Pythagoras was written centuries after he lived. He was born on the island of Samos, and travelled, visiting Egypt and Greece, around 530 BC, he moved to Croton, in Magna Graecia, and there established some kind of school or guild. In 520 BC, he returned to Samos, Pythagoras made influential contributions to philosophy and religion in the late 6th century BC. He is often revered as a mathematician and scientist and is best known for the Pythagorean theorem which bears his name. Many of the accomplishments credited to Pythagoras may actually have been accomplishments of his colleagues, some accounts mention that the philosophy associated with Pythagoras was related to mathematics and that numbers were important. It was said that he was the first man to himself a philosopher, or lover of wisdom, and Pythagorean ideas exercised a marked influence on Plato. Burkert states that Aristoxenus and Dicaearchus are the most important accounts, Aristotle had written a separate work On the Pythagoreans, which is no longer extant. However, the Protrepticus possibly contains parts of On the Pythagoreans and his disciples Dicaearchus, Aristoxenus, and Heraclides Ponticus had written on the same subject. These writers, late as they are, were among the best sources from whom Porphyry and Iamblichus drew, while adding some legendary accounts. Herodotus, Isocrates, and other writers agree that Pythagoras was the son of Mnesarchus and born on the Greek island of Samos. His father is said to have been a gem-engraver or a wealthy merchant, a late source gives his mothers name as Pythais. As to the date of his birth, Aristoxenus stated that Pythagoras left Samos in the reign of Polycrates, at the age of 40, around 530 BC he arrived in the Greek colony of Croton in what was then Magna Graecia. There he founded his own school the members of which he engaged to a disciplined. He furthermore aquired some political influence, on Greeks and non-Greeks of the region, following a conflict with the neighbouring colony of Sybaris, internal discord drove most of the Pythagoreans out of Croton. Pythagoras left the city before the outbreak of civil unrest and moved to Metapontum, after his death, his house was transformed into a sanctuary of Demeter, out of veneration for the philosopher, by the local population. In ancient sources there was disagreement and inconsistency about the late life of Pythagoras. His tomb was shown at Metapontum in the time of Cicero, according to Walter Burkert, Most obvious is the contradiction between Aristoxenus and Dicaearchus, regarding the catastrophe that overwhelmed the Pythagorean society

43.
Parmenides
–
Parmenides of Elea was a pre-Socratic Greek philosopher from Elea in Magna Graecia. He was the founder of the Eleatic school of philosophy, the single known work of Parmenides is a poem, On Nature, which has survived only in fragmentary form. In this poem, Parmenides describes two views of reality, in the way of truth, he explains how reality is one, change is impossible, and existence is timeless, uniform, necessary, and unchanging. In the way of opinion, he explains the world of appearances, in which ones sensory faculties lead to conceptions which are false, Parmenides was born in the Greek colony of Elea, which, according to Herodotus, had been founded shortly before 535 BC. He was descended from a wealthy and illustrious family,450 BC, which, if true, suggests a year of birth of c.515 BC. He was said to have been a pupil of Xenophanes, and regardless of whether they knew each other. Diogenes Laërtius also describes Parmenides as a disciple of Ameinias, son of Diochaites, the Pythagorean, the first hero cult of a philosopher we know of was Parmenides dedication of a heroon to his teacher Ameinias in Elea. Parmenides was the founder of the School of Elea, which also included Zeno of Elea, of his life in Elea, it was said that he had written the laws of the city. His most important pupil was Zeno, who according to Plato was 25 years his junior, Parmenides had a large influence on Plato, who not only named a dialogue, Parmenides, after him, but always spoke of him with veneration. William Smith also wrote in Dictionary of Greek and Roman Biography and Mythology, Reason is our guide, on the latter the eye that does not catch the object and re-echoing hearing. Thought and that which is thought of coinciding, the passages of Plato, Aristotle, Theophrastus, and others. Parmenides is one of the most significant of the pre-Socratic philosophers and his single known work, a poem conventionally titled On Nature, has survived only in fragments. Approximately 160 verses remain today from a total that was probably near 800. The poem was divided into three parts, A proem, which introduced the entire work, A section known as The Way of Truth. The proem is a sequence in which the narrator travels beyond the beaten paths of mortal men to receive a revelation from an unnamed goddess on the nature of reality. Aletheia, an estimated 90% of which has survived, and doxa, in the proem, Parmenides describes the journey of the poet, escorted by maidens, from the ordinary daytime world to a strange destination, outside our human paths. Carried in a chariot, and attended by the daughters of Helios the Sun. The goddess resides in a well-known mythological space, where Night and its essential character is that here all opposites are undivided, or one

44.
Empedocles
–
Empedocles was a Greek pre-Socratic philosopher and a citizen of Acragas, a Greek city in Sicily. Empedocles philosophy is best known for originating the theory of the four classical elements. He also proposed forces he called Love and Strife which would mix as well as separate the elements and these physical speculations were part of a history of the universe which also dealt with the origin and development of life. Influenced by the Pythagoreans, Empedocles was a vegetarian who supported the doctrine of reincarnation and he is generally considered the last Greek philosopher to have recorded his ideas in verse. Some of his survives, more than is the case for any other pre-Socratic philosopher. Empedocles death was mythologized by ancient writers, and has been the subject of a number of literary treatments, Empedocles was born, c.490 BC, at Acragas in Sicily to a distinguished family. Very little is known about his life and his father Meto seems to have been instrumental in overthrowing the tyrant of Agrigentum, presumably Thrasydaeus in 470 BC. Empedocles continued this tradition by helping to overthrow the succeeding oligarchic government, Empedocles was acquainted or connected by friendship with the physicians Pausanias and Acron, with various Pythagoreans, and even, it is said, with Parmenides and Anaxagoras. The only pupil of Empedocles who is mentioned is the sophist, according to Aristotle, he died at the age of sixty, even though other writers have him living up to the age of one hundred and nine. The contemporary Life of Empedocles by Xanthus has been lost, Empedocles is considered the last Greek philosopher to write in verse and the surviving fragments of his teaching are from two poems, Purifications and On Nature. Lucretius speaks of him with enthusiasm, and evidently viewed him as his model, the two poems together comprised 5000 lines. About 550 lines of his survive, although because ancient writers rarely mentioned which poem they were quoting. Some scholars now believe there was only one poem. We possess only about 100 lines of his Purifications and it seems to have given a mythical account of the world which may, nevertheless, have been part of Empedocles philosophical system. Humans, animals, and even plants are such spirits, the moral conduct recommended in the poem may allow us to become like gods again. There are about 450 lines of his poem On Nature extant, the poem originally consisted of 2000 lines of hexameter verse, and was addressed to Pausanias. It was this poem which outlined his philosophical system, although acquainted with the theories of the Eleatics and the Pythagoreans, Empedocles did not belong to any one definite school. An eclectic in his thinking, he combined much that had been suggested by Parmenides, Pythagoras and he was a firm believer in Orphic mysteries, as well as a scientific thinker and a precursor of physical science

45.
Pythagoreanism
–
Later revivals of Pythagorean doctrines led to what is now called Neopythagoreanism or Neoplatonism. Pythagorean ideas exercised an influence on Aristotle, and Plato. According to tradition, pythagoreanism developed at some point into two schools of thought, the mathēmatikoi and the akousmatikoi. There is the inner and outer circle John Burnet noted Lastly, we have one admitted instance of a philosophic guild, that of the Pythagoreans. And it will be found that the hypothesis, if it is to be called by that name, of a regular organisation of scientific activity will alone explain all the facts. The development of doctrine in the hands of Thales, Anaximander, according to Iamblichus in The life of Pythagoras, by Thomas Taylor There were also two forms of philosophy, for the two genera of those that pursued it, the Acusmatici and the Mathematici. The latter are acknowledged to be Pythagoreans by the rest but the Mathematici do not admit that the Acusmatici derived their instructions from Pythagoras, memory was the most valued faculty. All these auditions were of three kinds, some signifying what a thing is, others what it especially is, others what ought or ought not to be done. By musical sounds alone unaccompanied with words they healed the passions of the soul and certain diseases, enchanting in reality and it is probable that from hence this name epode, i. e. enchantment, came to be generally used. Each of these he corrected through the rule of virtue, attempering them through appropriate melodies, therefore its function is none of what are called ‘parts of virtue’, for it is better than all of them and the end produced is always better than the knowledge that produces it. Nor is every virtue of the soul in that way a function, nor is success, for if it is to be productive, different ones will produce different things, as the skill of building produces a house. However, intelligence is a part of virtue and of success, according to historians like Thomas Gale, Thomas Taler, or Cantor, Archytas became the head of the school, about a century after the murder of Pythagoras. According to August Böckh, who cites Nicomachus, Philolaus was the successor of Pythagoras, and according to Cicero, Philolaus was teacher of Archytas of Tarentum. According to the historians from the Stanford Encyclopedia of Philosophy, Philolaus and Eurytus are identified by Aristoxenus as teachers of the last generation of Pythagoreans, a Echecrates is mentioned by Aristoxenus as a student of Philolaus and Eurytus. The mathēmatikoi were supposed to have extended and developed the more mathematical, the mathēmatikoi did think that the akousmatikoi were Pythagorean, but felt that their own group was more representative of Pythagoras. Commentary from Sir William Smith, Dictionary of Greek and Roman Biography, Aristotle states the fundamental maxim of the Pythagoreans in various forms. According to Philolaus, number is the dominant and self-produced bond of the continuance of things. But number has two forms, the even and the odd, and a third, resulting from the mixture of the two, the even-odd and this third species is one itself, for it is both even and odd

46.
Plato
–
Plato was a philosopher in Classical Greece and the founder of the Academy in Athens, the first institution of higher learning in the Western world. He is widely considered the most pivotal figure in the development of philosophy, unlike nearly all of his philosophical contemporaries, Platos entire work is believed to have survived intact for over 2,400 years. Along with his teacher, Socrates, and his most famous student, Aristotle, Plato laid the foundations of Western philosophy. Alfred North Whitehead once noted, the safest general characterization of the European philosophical tradition is that it consists of a series of footnotes to Plato. In addition to being a figure for Western science, philosophy. Friedrich Nietzsche, amongst other scholars, called Christianity, Platonism for the people, Plato was the innovator of the written dialogue and dialectic forms in philosophy, which originate with him. He was not the first thinker or writer to whom the word “philosopher” should be applied, few other authors in the history of Western philosophy approximate him in depth and range, perhaps only Aristotle, Aquinas and Kant would be generally agreed to be of the same rank. Due to a lack of surviving accounts, little is known about Platos early life, the philosopher came from one of the wealthiest and most politically active families in Athens. Ancient sources describe him as a bright though modest boy who excelled in his studies, the exact time and place of Platos birth are unknown, but it is certain that he belonged to an aristocratic and influential family. Based on ancient sources, most modern scholars believe that he was born in Athens or Aegina between 429 and 423 BCE. According to a tradition, reported by Diogenes Laertius, Ariston traced his descent from the king of Athens, Codrus. Platos mother was Perictione, whose family boasted of a relationship with the famous Athenian lawmaker, besides Plato himself, Ariston and Perictione had three other children, these were two sons, Adeimantus and Glaucon, and a daughter Potone, the mother of Speusippus. The brothers Adeimantus and Glaucon are mentioned in the Republic as sons of Ariston, and presumably brothers of Plato, but in a scenario in the Memorabilia, Xenophon confused the issue by presenting a Glaucon much younger than Plato. Then, at twenty-eight, Hermodorus says, went to Euclides in Megara, as Debra Nails argues, The text itself gives no reason to infer that Plato left immediately for Megara and implies the very opposite. Thus, Nails dates Platos birth to 424/423, another legend related that, when Plato was an infant, bees settled on his lips while he was sleeping, an augury of the sweetness of style in which he would discourse about philosophy. Ariston appears to have died in Platos childhood, although the dating of his death is difficult. Perictione then married Pyrilampes, her mothers brother, who had served many times as an ambassador to the Persian court and was a friend of Pericles, Pyrilampes had a son from a previous marriage, Demus, who was famous for his beauty. Perictione gave birth to Pyrilampes second son, Antiphon, the half-brother of Plato and these and other references suggest a considerable amount of family pride and enable us to reconstruct Platos family tree

47.
Italy
–
Italy, officially the Italian Republic, is a unitary parliamentary republic in Europe. Located in the heart of the Mediterranean Sea, Italy shares open land borders with France, Switzerland, Austria, Slovenia, San Marino, Italy covers an area of 301,338 km2 and has a largely temperate seasonal and Mediterranean climate. Due to its shape, it is referred to in Italy as lo Stivale. With 61 million inhabitants, it is the fourth most populous EU member state, the Italic tribe known as the Latins formed the Roman Kingdom, which eventually became a republic that conquered and assimilated other nearby civilisations. The legacy of the Roman Empire is widespread and can be observed in the distribution of civilian law, republican governments, Christianity. The Renaissance began in Italy and spread to the rest of Europe, bringing a renewed interest in humanism, science, exploration, Italian culture flourished at this time, producing famous scholars, artists and polymaths such as Leonardo da Vinci, Galileo, Michelangelo and Machiavelli. The weakened sovereigns soon fell victim to conquest by European powers such as France, Spain and Austria. Despite being one of the victors in World War I, Italy entered a period of economic crisis and social turmoil. The subsequent participation in World War II on the Axis side ended in defeat, economic destruction. Today, Italy has the third largest economy in the Eurozone and it has a very high level of human development and is ranked sixth in the world for life expectancy. The country plays a prominent role in regional and global economic, military, cultural and diplomatic affairs, as a reflection of its cultural wealth, Italy is home to 51 World Heritage Sites, the most in the world, and is the fifth most visited country. The assumptions on the etymology of the name Italia are very numerous, according to one of the more common explanations, the term Italia, from Latin, Italia, was borrowed through Greek from the Oscan Víteliú, meaning land of young cattle. The bull was a symbol of the southern Italic tribes and was often depicted goring the Roman wolf as a defiant symbol of free Italy during the Social War. Greek historian Dionysius of Halicarnassus states this account together with the legend that Italy was named after Italus, mentioned also by Aristotle and Thucydides. The name Italia originally applied only to a part of what is now Southern Italy – according to Antiochus of Syracuse, but by his time Oenotria and Italy had become synonymous, and the name also applied to most of Lucania as well. The Greeks gradually came to apply the name Italia to a larger region, excavations throughout Italy revealed a Neanderthal presence dating back to the Palaeolithic period, some 200,000 years ago, modern Humans arrived about 40,000 years ago. Other ancient Italian peoples of undetermined language families but of possible origins include the Rhaetian people and Cammuni. Also the Phoenicians established colonies on the coasts of Sardinia and Sicily, the Roman legacy has deeply influenced the Western civilisation, shaping most of the modern world

48.
Pythagorean mathematics
–
Later revivals of Pythagorean doctrines led to what is now called Neopythagoreanism or Neoplatonism. Pythagorean ideas exercised an influence on Aristotle, and Plato. According to tradition, pythagoreanism developed at some point into two schools of thought, the mathēmatikoi and the akousmatikoi. There is the inner and outer circle John Burnet noted Lastly, we have one admitted instance of a philosophic guild, that of the Pythagoreans. And it will be found that the hypothesis, if it is to be called by that name, of a regular organisation of scientific activity will alone explain all the facts. The development of doctrine in the hands of Thales, Anaximander, according to Iamblichus in The life of Pythagoras, by Thomas Taylor There were also two forms of philosophy, for the two genera of those that pursued it, the Acusmatici and the Mathematici. The latter are acknowledged to be Pythagoreans by the rest but the Mathematici do not admit that the Acusmatici derived their instructions from Pythagoras, memory was the most valued faculty. All these auditions were of three kinds, some signifying what a thing is, others what it especially is, others what ought or ought not to be done. By musical sounds alone unaccompanied with words they healed the passions of the soul and certain diseases, enchanting in reality and it is probable that from hence this name epode, i. e. enchantment, came to be generally used. Each of these he corrected through the rule of virtue, attempering them through appropriate melodies, therefore its function is none of what are called ‘parts of virtue’, for it is better than all of them and the end produced is always better than the knowledge that produces it. Nor is every virtue of the soul in that way a function, nor is success, for if it is to be productive, different ones will produce different things, as the skill of building produces a house. However, intelligence is a part of virtue and of success, according to historians like Thomas Gale, Thomas Taler, or Cantor, Archytas became the head of the school, about a century after the murder of Pythagoras. According to August Böckh, who cites Nicomachus, Philolaus was the successor of Pythagoras, and according to Cicero, Philolaus was teacher of Archytas of Tarentum. According to the historians from the Stanford Encyclopedia of Philosophy, Philolaus and Eurytus are identified by Aristoxenus as teachers of the last generation of Pythagoreans, a Echecrates is mentioned by Aristoxenus as a student of Philolaus and Eurytus. The mathēmatikoi were supposed to have extended and developed the more mathematical, the mathēmatikoi did think that the akousmatikoi were Pythagorean, but felt that their own group was more representative of Pythagoras. Commentary from Sir William Smith, Dictionary of Greek and Roman Biography, Aristotle states the fundamental maxim of the Pythagoreans in various forms. According to Philolaus, number is the dominant and self-produced bond of the continuance of things. But number has two forms, the even and the odd, and a third, resulting from the mixture of the two, the even-odd and this third species is one itself, for it is both even and odd

Earth radius
–
Earth radius is the distance from the Earths center to its surface, about 6,371 km. This length is used as a unit of distance, especially in astronomy and geology. This article deals primarily with spherical and ellipsoidal models of the Earth, see Figure of the Earth for a more complete discussion of the models. The Earth is only approximately sph

1.
For the historical development of the concept, see Spherical Earth.

2.
Scale drawing of the oblateness of the 2003 IERS reference ellipsoid. The outer edge of the dark blue line is an ellipse with the same eccentricity as that of the Earth, with north at the top. For comparison, the outer edge of light blue area is a circle of diameter equal to the minor axis. The red line denotes the Karman line and the yellow area, the range of the International Space Station.

Medieval
–
In the history of Europe, the Middle Ages or Medieval Period lasted from the 5th to the 15th century. It began with the fall of the Western Roman Empire and merged into the Renaissance, the Middle Ages is the middle period of the three traditional divisions of Western history, classical antiquity, the medieval period, and the modern period. The med

1.
The Cross of Mathilde, a crux gemmata made for Mathilde, Abbess of Essen (973–1011), who is shown kneeling before the Virgin and Child in the enamel plaque. The body of Christ is slightly later. Probably made in Cologne or Essen, the cross demonstrates several medieval techniques: cast figurative sculpture, filigree, enamelling, gem polishing and setting, and the reuse of Classical cameos and engraved gems.

2.
A late Roman statue depicting the four Tetrarchs, now in Venice

3.
Coin of Theodoric

4.
Mosaic showing Justinian with the bishop of Ravenna, bodyguards, and courtiers

Earth
–
Earth, otherwise known as the World, or the Globe, is the third planet from the Sun and the only object in the Universe known to harbor life. It is the densest planet in the Solar System and the largest of the four terrestrial planets, according to radiometric dating and other sources of evidence, Earth formed about 4.54 billion years ago. Earths g

1.
" The Blue Marble " photograph of Earth, taken during the Apollo 17 lunar mission in 1972

2.
Artist's impression of the early Solar System's planetary disk

3.
World map color-coded by relative height

4.
The summit of Chimborazo, in Ecuador, is the point on Earth's surface farthest from its center.

Water
–
Water is a transparent and nearly colorless chemical substance that is the main constituent of Earths streams, lakes, and oceans, and the fluids of most living organisms. Its chemical formula is H2O, meaning that its molecule contains one oxygen, Water strictly refers to the liquid state of that substance, that prevails at standard ambient temperat

1.
Water in three states: liquid, solid (ice), and gas (invisible water vapor in the air). Clouds are accumulations of water droplets, condensed from vapor-saturated air.

2.
Impact from a water drop causes an upward "rebound" jet surrounded by circular capillary waves.

3.
Snowflakes by Wilson Bentley, 1902.

4.
Dew drops adhering to a spider web.

Greek philosophy
–
Ancient Greek philosophy arose in the 6th century BC and continued throughout the Hellenistic period and the period in which Ancient Greece was part of the Roman Empire. Philosophy was used to sense out of the world in a non-religious way. It dealt with a variety of subjects, including political philosophy, ethics, metaphysics, ontology, logic, bio

History of geodesy
–
Geodesy, also named geodetics, is the scientific discipline that deals with the measurement and representation of the Earth. The history of geodesy began in antiquity and blossomed during the Age of Enlightenment, early ideas about the figure of the Earth held the Earth to be flat, and the heavens a physical dome spanning over it. The early Greeks,

1.
Archive with lithography plates for maps of Bavaria in the Landesamt für Vermessung und Geoinformation in Munich

2.
Geodesy

3.
Negative lithography stone and positive print of a historic map of Munich

Figure of the Earth
–
The expression figure of the Earth has various meanings in geodesy according to the way it is used and the precision with which the Earths size and shape is to be defined. The actual topographic surface is most apparent with its variety of land forms and this is, in fact, the surface on which actual Earth measurements are made. The topographic surf

1.
The curvature of Earth as seen in Valencia, Spain (Playa de la Malvarrosa)

2.
An oblate spheroid

Old World
–
The Old World consists of Africa, Europe, and Asia, regarded collectively as the part of the world known to Europeans before contact with the Americas. It is used in the context of, and contrast with and these regions were connected via the Silk Road trade route, and they have a pronounced Iron Age period following the Bronze Age. The concept of th

1.
Map of the "Old World" (the Ptolemy world map in a 15th-century copy)

Late Antiquity
–
Late antiquity is a periodization used by historians to describe the time of transition from classical antiquity to the Middle Ages in mainland Europe, the Mediterranean world, and the Near East. The development of the periodization has generally been accredited to historian Peter Brown, precise boundaries for the period are a continuing matter of

1.
The Barberini ivory, a late Leonid / Justinian Byzantine ivory leaf from an imperial diptych, from an imperial workshop in Constantinople in the first half of the sixth century (Louvre Museum)

2.
Modern statue of Constantine I at York, where he was proclaimed Augustus in 306.

3.
The Favourites of the Emperor Honorius, 1883: John William Waterhouse expresses the sense of moral decadence that coloured the 19th-century historical view of the 5th century.

4.
View west along the Harbour Street towards the Library of Celsus in Ephesus. The pillars on the left side of the street were part of the colonnaded walkway apparent in cities of Late Antique Asia Minor.

Middle Ages
–
In the history of Europe, the Middle Ages or Medieval Period lasted from the 5th to the 15th century. It began with the fall of the Western Roman Empire and merged into the Renaissance, the Middle Ages is the middle period of the three traditional divisions of Western history, classical antiquity, the medieval period, and the modern period. The med

1.
The Cross of Mathilde, a crux gemmata made for Mathilde, Abbess of Essen (973–1011), who is shown kneeling before the Virgin and Child in the enamel plaque. The body of Christ is slightly later. Probably made in Cologne or Essen, the cross demonstrates several medieval techniques: cast figurative sculpture, filigree, enamelling, gem polishing and setting, and the reuse of Classical cameos and engraved gems.

2.
A late Roman statue depicting the four Tetrarchs, now in Venice

3.
Coin of Theodoric

4.
Mosaic showing Justinian with the bishop of Ravenna, bodyguards, and courtiers

Ferdinand Magellan
–
Commanding a fleet of five vessels, he headed south through the Atlantic Ocean to Patagonia, passing through the Strait of Magellan into a body of water he named the peaceful sea. Despite a series of storms and mutinies, the reached the Spice Islands in 1521. Magellan did not complete the voyage, as he was killed during the Battle of Mactan in the

3.
The Strait of Magellan cuts through the southern tip of South America connecting the Atlantic Ocean and Pacific Ocean.

4.
Monument in Lapu-Lapu City, Cebu in the Philippines.

Circumnavigation
–
Circumnavigation means to travel all the way around the entire planet, or an island, or continent. This article is concerned with circumnavigation of the Earth, the first known circumnavigation of Earth was the Magellan-Elcano expedition, which sailed from Seville, Spain, in 1519 and returned in 1522 after crossing the Atlantic, Pacific and Indian

1.
Jason Lewis of Expedition 360 pedaling his boat Moksha on the River Thames in London, shortly before completing the first human-powered circumnavigation of the Earth (2007)

2.
In 2012, the Swiss boat PlanetSolar became the first ever solar electric vehicle to circumnavigate the globe

3.
A replica of Magellan's Nao Victoria, the first vessel to circumnavigate the planet

Flat Earth
–
The flat Earth model is an archaic conception of the Earths shape as a plane or disk. The idea of a spherical Earth appeared in Greek philosophy with Pythagoras, Aristotle provided evidence for the spherical shape of the Earth on empirical grounds by around 330 BC. Knowledge of the spherical Earth gradually began to spread beyond the Hellenistic wo

1.
The Flammarion engraving (1888) depicts a traveler who arrives at the edge of a flat Earth and sticks his head through the firmament.

3.
When a ship is at the horizon, its lower part is obscured due to the curvature of the Earth.

4.
Cosmas Indicopleustes' world view – flat earth in a Tabernacle

Mesopotamian mythology
–
The religious development of Mesopotamia and Mesopotamian culture in general was not particularly influenced by the movements of the various peoples into and throughout the area. Rather, Mesopotamian religion was a consistent and coherent tradition which adapted to the needs of its adherents over millenia of development. The earliest undercurrents

1.
The god Marduk and his dragon Mušḫuššu

2.
Representation of the Goddess Ishtar, winged and wearing a version of the horned cap of divinity. Detail of the so-called "Ishtar vase", early 2nd millennium BCE (Louvre AO 17000)

3.
Geography

Early world maps
–
The earliest known world maps date to classical antiquity, the oldest examples of the 6th to 5th centuries BCE still based on the flat Earth paradigm. World maps assuming a spherical Earth first appear in the Hellenistic period, a Babylonian world map, known as the Imago Mundi, is commonly dated to the 6th century BCE. The accompanying text mention

3.
A 1628 reconstruction of Posidonius ideas about the positions of continents (many details couldn't have been known by Posidonius)

4.
An 1898 reconstruction of Pomponius Melas view of the World.

Anaximander
–
Anaximander was a pre-Socratic Greek philosopher who lived in Miletus, a city of Ionia. He belonged to the Milesian school and learned the teachings of his master Thales and he succeeded Thales and became the second master of that school where he counted Anaximenes and, arguably, Pythagoras amongst his pupils. Little of his life and work is known t

1.
Relief representing Anaximander (Roma, Museo Nazionale Romano). Probably Roman copy of an earlier Greek original. This is the only existing image of Anaximander from the ancient world.

2.
Detail of Raphael 's painting The School of Athens, 1510–1511. This could be a representation of Anaximander leaning towards Pythagoras on his left.

Hecataeus of Miletus
–
Hecataeus of Miletus, son of Hagesandrus, was an early Greek historian and geographer. Hailing from a family, he lived in Miletus, then under Persian rule. He was active during the time of the Greco-Persian Wars, after having travelled extensively, he settled in his native city, where he occupied a high position, and devoted his time to the composi

1.
Reconstruction of Hecataeus' map

Ziggurat
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A ziggurat was a massive structure built in ancient Mesopotamia and the western Iranian plateau. It had the form of a step pyramid of successively receding stories or levels. Notable ziggurats include the Great Ziggurat of Ur near Nasiriyah, the Ziggurat of Aqar Quf near Baghdad, Ziggurats were built by the ancient Sumerians, Babylonians, Elamites,

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The reconstructed facade of the Neo-Sumerian Great Ziggurat of Ur, near Nasiriyah, Iraq

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CAD rendering of Sialk 's largest ziggurat based on archeological evidence.

Cosmic mountain
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The axis mundi, in certain beliefs and philosophies, is the world center, or the connection between Heaven and Earth. As the celestial pole and geographic pole, it expresses a point of connection between sky and earth where the four directions meet. At this point travel and correspondence is made higher and lower realms. Communication from lower re

Avesta
–
The Avesta /əˈvɛstə/ is the primary collection of religious texts of Zoroastrianism, composed in the otherwise unrecorded Avestan language. The Avesta texts fall into different categories, arranged either by dialect. The principal text in the group is the Yasna, which takes its name from the Yasna ceremony, Zoroastrianisms primary act of worship. T

1.
Yasna 28.1 (Bodleian MS J2)

Persian Empire
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Persian Empire refers to any of a series of imperial dynasties centered in Persia. The first of these was the Achaemenid Empire established by Cyrus the Great in 550 BC with the conquest of Median, Lydian and Babylonian empires and it covered much of the Ancient world when it was conquered by Alexander the Great. Several later dynasties claimed to

1.
Extent of the first Persian Empire, the Achaemenid Empire.

Earth ellipsoid
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An Earth ellipsoid is a mathematical figure approximating the shape of the Earth, used as a reference frame for computations in geodesy, astronomy and the geosciences. Various different ellipsoids have been used as approximations and it is an ellipsoid of revolution, whose short axis is approximately aligned with the rotation axis of the Earth. The

1.
Geodesy

Isaac Newton
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His book Philosophiæ Naturalis Principia Mathematica, first published in 1687, laid the foundations of classical mechanics. Newton also made contributions to optics, and he shares credit with Gottfried Wilhelm Leibniz for developing the infinitesimal calculus. Newtons Principia formulated the laws of motion and universal gravitation that dominated

4.
Replica of Newton's second Reflecting telescope that he presented to the Royal Society in 1672

Jean Baptiste Joseph Delambre
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Jean Baptiste Joseph, chevalier Delambre was a French mathematician and astronomer. He was also director of the Paris Observatory, and author of books on the history of astronomy from ancient times to the 18th century. After a childhood fever, he suffered from very sensitive eyes, for fear of losing his ability to read, he devoured any book availab

1.
Jean Baptiste Joseph Delambre

George Everest
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Colonel Sir George Everest FRS, FRAS was a Welsh surveyor and geographer, and the Surveyor General of India from 1830 through 1843. This survey was started by William Lambton in 1806 and it lasted for several decades, in 1865, Mount Everest was named in his honour in the English language, despite his objections, by the Royal Geographical Society. T

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Photograph of Everest

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Everest's grave, St Andrew's, Hove

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George Everest house

United States Department of Defense
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The Department is the largest employer in the world, with nearly 1.3 million active duty servicemen and women as of 2016. Adding to its employees are over 801,000 National Guardsmen and Reservists from the four services and it is headquartered at the Pentagon in Arlington, Virginia, just outside of Washington, D. C. The Department of Defense is hea

1.
The Pentagon, headquarters of the U.S. Department of Defense

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Department of Defense

3.
President Harry Truman signs the National Security Act Amendment of 1949

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Department of Defense organizational chart (December 2013)

World Geodetic System
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The World Geodetic System is a standard for use in cartography, geodesy, and navigation including GPS. It comprises a standard system for the Earth, a standard spheroidal reference surface for raw altitude data. The latest revision is WGS84, established in 1984 and last revised in 2004, earlier schemes included WGS72, WGS66, and WGS60. WGS84 is the

Altitude
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Altitude or height is defined based on the context in which it is used. As a general definition, altitude is a measurement, usually in the vertical or up direction. The reference datum also often varies according to the context, although the term altitude is commonly used to mean the height above sea level of a location, in geography the term eleva

1.
Vertical distance comparison

Greek colonies
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Colonies in antiquity were city-states founded from a mother-city, not from a territory-at-large. Bonds between a colony and its metropolis remained often close, and took specific forms, however, unlike in the period of European colonialism during the early and late modern era, ancient colonies were usually sovereign and self-governing from their i

1.
The Mediterranean in ca. the 6th century BC. Phoenician cities are labelled in yellow, Greek cities in red, and other cities in grey.

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Map showing the Augustus "roman coloniae" in north Africa

Mediterranean Sea
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The sea is sometimes considered a part of the Atlantic Ocean, although it is usually identified as a separate body of water. The name Mediterranean is derived from the Latin mediterraneus, meaning inland or in the middle of land and it covers an approximate area of 2.5 million km2, but its connection to the Atlantic is only 14 km wide. The Strait o

1.
Circa the 6th century BCE: In ancient times the Mediterranean provided sources of food and local commerce and direct routes for trade and communications, colonisation, and war. Numerous cities and colonies were situated at its shores or within the basin: Greek (red) and Phoenician (yellow) colonies in antiquity; and other cities (grey), including the provincial "Rom".

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Map of the Mediterranean Sea

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With its highly indented coastline and large number of islands, Greece has the longest Mediterranean coastline.

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The Battle of Lepanto, 1571, ended in victory for the European Holy League against the Ottoman Turks.

Nile Delta
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The Nile Delta is the delta formed in Northern Egypt where the Nile River spreads out and drains into the Mediterranean Sea. It is one of the worlds largest river deltas—from Alexandria in the west to Port Said in the east, from north to south the delta is approximately 160 kilometres in length. The Delta begins slightly down-river from Cairo, from

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NASA satellite photograph of the Nile Delta (shown in false color)

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The Nile Delta at night

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Nile River and Delta

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Ancient branches of the Nile, showing Wadi Tumilat, and the lakes east of the Delta

Crimea
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The peninsula is located south of the Ukrainian region of Kherson and west of the Russian region of Kuban. It is connected to Kherson Oblast by the Isthmus of Perekop and is separated from Kuban by the Strait of Kerch, the Arabat Spit is located to the northeast, a narrow strip of land that separates a system of lagoons named Sivash from the Sea of

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Ruins of ancient Greek colony of Chersonesos

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Satellite image of the Crimean peninsula

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Swallow's Nest, built in 1912 for oil millionaire Baron von Steingel, a landmark of Crimea

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Armenian monastery of the Holy Cross (Սուրբ Խաչ), established in 1358

Herodotus
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Herodotus was a Greek historian who was born in Halicarnassus in the Persian Empire and lived in the fifth century BC, a contemporary of Socrates. The Histories is the work which he is known to have produced. Despite Herodotus historical significance, little is known of his personal life and his place in history and his significance may be understo

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A Roman copy (2nd century AD) of a Greek bust of Herodotus from the first half of the 4th century BC

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Fragment from the Histories VIII on Papyrus Oxyrhynchus 2099, early 2nd century AD

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Relief of Herodotus by Jean-Guillaume Moitte (1806), Louvre, Paris

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The statue of Herodotus in his hometown of Halicarnassus, modern Bodrum, Turkey.

Africa
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Africa is the worlds second-largest and second-most-populous continent. At about 30.3 million km² including adjacent islands, it covers 6% of Earths total surface area and 20.4 % of its land area. With 1.2 billion people as of 2016, it accounts for about 16% of the human population. The continent includes Madagascar and various archipelagos and it

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Map of Africa

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Africa

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Lucy, an Australopithecus afarensis skeleton discovered on November 24, 1974, in the Awash Valley of Ethiopia 's Afar Depression

Phoenicia
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The enterprising, sea-based Phoenician civilization spread across the Mediterranean between 1500 BC and 300 BC. Their civilization was organized in city-states, similar to those of Ancient Greece, perhaps the most notable of which were Tyre, Sidon, Arvad, Berytus and Carthage. Each city-state was an independent unit, and it is uncertain to what ext

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Sarcophagus of Eshmunazor II, Phoenician King of Sidon found near Sidon, in southern Lebanon

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Map of Phoenicia and its Mediterranean trade routes

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Assyrian warship (probably built by Phoenicians) with two rows of oars, relief from Nineveh, c. 700 BC

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A naval action during the siege of Tyre (350 BC). Drawing by André Castaigne, 1888–1889.

Ancient Egypt
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Ancient Egypt was a civilization of ancient Northeastern Africa, concentrated along the lower reaches of the Nile River in what is now the modern country of Egypt. It is one of six civilizations to arise independently, Egyptian civilization followed prehistoric Egypt and coalesced around 3150 BC with the political unification of Upper and Lower Egy

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The Great Sphinx and the pyramids of Giza are among the most recognizable symbols of the civilization of ancient Egypt.

Pharaoh
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The word pharaoh ultimately derive from the Egyptian compound pr-ˤ3 great house, written with the two biliteral hieroglyphs pr house and ˤ3 column, here meaning great or high. It was used only in larger phrases such as smr pr-ˤ3 Courtier of the High House, with specific reference to the buildings of the court or palace. From the twelfth dynasty onw

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Den

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Narmer Palette

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Nomen and prenomen of Ramesses III

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Royal titulary

Necho II
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Necho II of Egypt was a king of the 26th Dynasty. Necho undertook a number of projects across his kingdom. In his reign, according to the Greek historian Herodotus, Necho II sent out an expedition of Phoenicians and his son, Psammetichus II, upon succession may have removed Nechos name from monuments. Necho played a significant role in the historie

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Aerial view of Tel Megiddo site of the battle of Megiddo in 609 BC.

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A small kneeling bronze statuette, likely Necho II, now residing in the Brooklyn Museum

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The world according to Herodotus, 440 BC

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A 15th-century depiction of the Ptolemy world map, reconstituted from Ptolemy's Geographia (c. 150)

Hebrew Bible
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They are composed mainly in Biblical Hebrew, with some passages in Biblical Aramaic. The term does not comment upon the naming, numbering or ordering of books, the term Hebrew Bible is an attempt to provide specificity with respect to contents but avoid allusion to any particular interpretative tradition or theological school of thought. Hebrew Bib

1.
Page from an 11th-century Aramaic Targum manuscript of the Hebrew Bible.

Shamayim
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Shamayim, the Hebrew word for heaven, denotes one component of the three-part cosmos, the other elements being erets and sheol. The Hebrew word shamayim is constructed of two parts, sham derived from Akkadian samu meaning sky or lofty, and Hebrew mayim meaning water, in Genesis 1,6 Elohim separated the water from the water. The area above the earth

1.
Flammarion engraving, Paris 1888

Sheol
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The inhabitants of Sheol are the shades, entities without personality or strength. Under some circumstances they are thought to be able to be contacted by the living, as the Witch of Endor contacts the shade of Samuel for Saul, but such practices are forbidden. While the Old Testament writings appear to describe Sheol as the permanent place of the

1.
The parable of the Rich man and Lazarus depicting the rich man in hell asking for help to Abraham by James Tissot

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Rapid Transit to Sheol - Where We Are All Going According to the Reverend Dr. Morgan Dix, by Joseph Keppler, 1888.

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Mictlan

Pythagoras
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Pythagoras of Samos was an Ionian Greek philosopher, mathematician, and the putative founder of the movement called Pythagoreanism. Most of the information about Pythagoras was written centuries after he lived. He was born on the island of Samos, and travelled, visiting Egypt and Greece, around 530 BC, he moved to Croton, in Magna Graecia, and ther

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Bust of Pythagoras of Samos in the Capitoline Museums, Rome.

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Bust of Pythagoras, Vatican

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A scene at the Chartres Cathedral shows a philosopher, on one of the archivolts over the right door of the west portal at Chartres, which has been attributed to depict Pythagoras.

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Croton on the southern coast of Magna Graecia (Southern Italy), to which Pythagoras ventured after feeling overburdened in Samos.

Parmenides
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Parmenides of Elea was a pre-Socratic Greek philosopher from Elea in Magna Graecia. He was the founder of the Eleatic school of philosophy, the single known work of Parmenides is a poem, On Nature, which has survived only in fragmentary form. In this poem, Parmenides describes two views of reality, in the way of truth, he explains how reality is on

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Parmenides

2.
Parmenides. Detail from The School of Athens by Raphael.

Empedocles
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Empedocles was a Greek pre-Socratic philosopher and a citizen of Acragas, a Greek city in Sicily. Empedocles philosophy is best known for originating the theory of the four classical elements. He also proposed forces he called Love and Strife which would mix as well as separate the elements and these physical speculations were part of a history of

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Empedocles, 17th-century engraving

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The temple of Hera at Agrigentum, built when Empedocles was a young man, c. 470 BC.

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A piece of the Strasbourg Empedocles papyrus in the Bibliothèque nationale et universitaire, Strasbourg

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Empedocles as portrayed in the Nuremberg Chronicle

Pythagoreanism
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Later revivals of Pythagorean doctrines led to what is now called Neopythagoreanism or Neoplatonism. Pythagorean ideas exercised an influence on Aristotle, and Plato. According to tradition, pythagoreanism developed at some point into two schools of thought, the mathēmatikoi and the akousmatikoi. There is the inner and outer circle John Burnet note

Plato
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Plato was a philosopher in Classical Greece and the founder of the Academy in Athens, the first institution of higher learning in the Western world. He is widely considered the most pivotal figure in the development of philosophy, unlike nearly all of his philosophical contemporaries, Platos entire work is believed to have survived intact for over

1.
Plato: copy of portrait bust by Silanion

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Plato from The School of Athens by Raphael, 1509

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Plato and Socrates in a medieval depiction

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Plato (left) and Aristotle (right), a detail of The School of Athens, a fresco by Raphael. Aristotle gestures to the earth, representing his belief in knowledge through empirical observation and experience, while holding a copy of his Nicomachean Ethics in his hand. Plato holds his Timaeus and gestures to the heavens, representing his belief in The Forms

Italy
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Italy, officially the Italian Republic, is a unitary parliamentary republic in Europe. Located in the heart of the Mediterranean Sea, Italy shares open land borders with France, Switzerland, Austria, Slovenia, San Marino, Italy covers an area of 301,338 km2 and has a largely temperate seasonal and Mediterranean climate. Due to its shape, it is refe

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The Colosseum in Rome, built c. 70 – 80 AD, is considered one of the greatest works of architecture and engineering of ancient history.

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Flag

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The Iron Crown of Lombardy, for centuries symbol of the Kings of Italy.

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Castel del Monte, built by German Emperor Frederick II, UNESCO World Heritage site

Pythagorean mathematics
–
Later revivals of Pythagorean doctrines led to what is now called Neopythagoreanism or Neoplatonism. Pythagorean ideas exercised an influence on Aristotle, and Plato. According to tradition, pythagoreanism developed at some point into two schools of thought, the mathēmatikoi and the akousmatikoi. There is the inner and outer circle John Burnet note

2.
Schematic diagram of the shadow cast by the Earth. Within the central umbra shadow, the moon is totally shielded from direct illumination by the Sun. In contrast, within the penumbra shadow, only a portion of Sunlight is blocked.

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A sphere has 2/3 the volume and surface area of its circumscribing cylinder including its bases. A sphere and cylinder were placed on the tomb of Archimedes at his request. (see also: Equiareal map)

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Transits of Venus across the face of the Sun were, for a long time, the best method of measuring the astronomical unit, despite the difficulties (here, the so-called " black drop effect ") and the rarity of observations.

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The red line indicates the Earth-Sun distance, which is on average about 1 astronomical unit.

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As shown by the tick marks, lines a and b are parallel. This can be proved because the transversal t produces congruent corresponding angles, shown here both to the right of the transversal, one above and adjacent to line a and the other above and adjacent to line b.

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Aristarchus's 3rd century BC calculations on the relative sizes of the Earth, Sun and Moon, from a 10th-century CE Greek copy

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Nicholas of Cusa, 15th century, asked whether there was any reason to assert that any point was the center of the universe.

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An illustration from al-Biruni 's astronomical works, explains the different phases of the moon, with respect to the position of the sun. Al-Biruni suggested that if the Earth rotated on its axis this would be consistent with astronomical theory. He discussed heliocentrism but considered it a problem of natural philosophy.

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Posidonius's method for calculating the circumference of the earth, relied on the altitude of the star Canopus

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World map according to ideas by Posidonius (150-130 BCE), drawn in 1628 by cartographers Petrus Bertius and Melchior Tavernier. Many of the details could not have been known to Posidonius; rather, Bertius and Tavernier show Posidonius's ideas about the positions of the continents.

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Posidonius, depicted as a medieval scholar in the Nuremberg Chronicle

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One of the Xanten Horse-Phalerae located in the British Museum, measuring 10.5 cm (4.1 in). It bears an inscription formed from punched dots: PLINIO PRAEF EQ; i.e., Plinio praefecto equitum, "Pliny prefect of cavalry". It was perhaps issued to every man in Pliny's unit. The figure is the bust of the emperor.

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Pliny the Elder, as imagined by a 19th-century artist. No contemporary depiction of Pliny is known to survive.

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City and Lake of Como, painted by Jean-Baptiste-Camille Corot, 1834.

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Engraving of a crowned Ptolemy being guided by the muse Astronomy, from Margarita Philosophica by Gregor Reisch, 1508. Although Abu Ma'shar believed Ptolemy to be one of the Ptolemies who ruled Egypt after the conquest of Alexander the title ‘King Ptolemy’ is generally viewed as a mark of respect for Ptolemy's elevated standing in science.

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Early Baroque artist's rendition

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A 15th-century manuscript copy of the Ptolemy world map, reconstituted from Ptolemy's Geography (circa 150), indicating the countries of " Serica " and "Sinae" (China) at the extreme east, beyond the island of "Taprobane" (Sri Lanka, oversized) and the "Aurea Chersonesus" (Malay Peninsula).

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The spherical coordinate system is commonly used in physics. It assigns three numbers (known as coordinates) to every point in Euclidean space: radial distance r, polar angle θ (theta), and azimuthal angle φ (phi). The symbol ρ (rho) is often used instead of r.

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A graticule on the Earth as a sphere or an ellipsoid. The lines from pole to pole are lines of constant longitude, or meridians. The circles parallel to the equator are lines of constant latitude, or parallels. The graticule determines the latitude and longitude of points on the surface. In this example meridians are spaced at 6° intervals and parallels at 4° intervals.